Guide:PvP



Player versus Player brings a unique type of play to the world of Terraria. This is a game mode where one player or a team of players can defeat another player or team of players. This is done by joining a multiplayer world, and enabling the PvP option by clicking on the swords in the upper right hand corner of the screen. The only way a player can damage another player is if both have the PvP option enabled. There is also the option of joining a team. Teams are represented by the colored shields in the upper left corner of the screen as well. Once you select a team there is an onscreen notification of how far away they are, as well as how much health they have. PvP is not an overly useful game mode as it does not help in any particular way. However it allows a very fun and challenging form of gameplay. Teamwork is usually the key factor in PvP combat, as it is also the key factor in Terraria! Below is a general guide as well as some tips, tricks, and hints that can help the average player become knowledgeable about the PvP factors in Terraria!

Damage
When attacking a player your damage is doubled. For instance, if you attack with a Muramasa, having a base damage of 22, and hit a player wearing a full set of molten armor, giving 27 defense, the damage dealt will be 30, as the damage is increased to 44 and the damage reduction is 14.

Weapons
PvP combat is always fast and always fierce; bringing top tier weapons is a must, but how can one decide on what to bring? Should one bring a flail or a sword, a gun or a bow? Here are some brief breakdowns of weapons sets that are advantageous (take into mind that only top tier weapons are included and described for space)!

Non-Magic Ranged
Bow & Arrow: Molten Fury + Jester's Arrow 38 damage, 25 use time (Sub in Unholy Arrow for 37 damage) this combo allows the player some utility, arrows arc creating a wider hit range, however their total flight time is not that great. A 1.52 max damage rate (or for the easy going player 1.44 using regular Wooden Arrows converted to Flaming Arrows). The major downside to this weapon is that high tier ammunition is hard to come by, and ultimately yields a small damage rate.

Gun & Ammo 1: Phoenix Blaster + Meteor Shot 37 damage, 10 use time (Sub in Musket Ball for 35 damage) This combo allows the player to quickly cause burst damage to the target it has a small hit range due to straight line travel; this is made up for in its long projectile flight time and its overall speed. A 3.7 damage rate is astoundingly good, yet the amount of ammunition consumed trying to hit a player may be very costly.

Gun & Ammo 2: Star Cannon + Fallen Star, 155 damage, 12 use time. This combo allows the player to deal an astounding amount of damage clocked in at 12.92 to an un-armored enemy (Unconfirmed). The downside to this is collecting stars is not quick process compared to the amount of ammunition consumed in a PvP fight, as well the stars cannot be reused. There is, however, a strategy for collecting fallen stars that requires a sky bridge.

Boomerang 1: Flamarang 32 damage, 15 use time This weapon allows the player an extra inventory slot due to not consuming ammunition, the downside is the projectiles very long return time if the target is missed. A plus side is that on the return the boomerang flies through bricks allowing the target to be hit from a safe location. A total damage rate of 2.14 leave this weapon open as a utility weapon.

Boomerang 2: Thorn Chakrum 25 damage, 15 use time The Thorn Chakrum deals slightly less damage than the Flamarang, with a 1.7 damage rate, but has the ability to bounce multiple times before returning to the user, making the weapon a great choice in tight quarters.

Melee Weapons
Sword 1: Fiery Greatsword 34 damage, use time of approx. 35-45. This weapon deals a bit of damage, and has a reach of about 10ft. A total damage rate of approx. .75-.95 makes this weapon hard to use in PvP effectively.

Sword 2: Blade of Grass 28 damage, use time of approx. 20-30. This weapon has an incredible reach of about 12ft. with a decent attack speed as well. A damage rate of approx. .93-1.4 making this weapon slightly more effective in combat.

Sword 3: Muramasa 22 damage, use time of approx. 10-15. This is probably one of the most effective PvP swords despite its initial low damage. The Muramasa has a damage rate of 1.467-2.2 being the highest actual damage output. This sword also has a very unique quality, if the melee key is held down the sword keeps swinging. This makes the sword very powerful in the right item set.

Flail: Sunfury 40 damage, use time of 30. This is known as the best non-projectile weapon in the game, it holds a high position in PvP combat due to flail mechanics. With a damage rate of 1.33 this weapon stands in high regard. A useful property of the flail mechanic is constant damage, as well as the flail traveling back through bricks on the way back to the player.

Magic Weapons
Magic 1: Vilethorn 8 damage (damage time interval unknown assumed 50), 5 mana, 30 use time This weapon isn't the ideal damage item, but can be extremely useful due to it being able to cause constant damage for a low amount of mana while also being able to attack through walls. With a damage rate of approx. .16, it should generally only be used for those 2 purposes.

Magic 2: Flamelash 41x2 damage, 20 mana, use time 20. This is arguably the best magic weapon regarding PvP due to its controllable projectile that may hit twice. With a damage rate of 3.5 this weapon stands out, however it does consume mana and one drastic downside is while controlling the projectile the player is rendered defenseless.

Magic 3: Starfury 15 damage (plus stars 20 each), 11 mana, 10 use time This weapon is a good addition to the PvP arsenal, but it only works when the character has mana (will not swing without mana, and only reaches maximum potential while outside or in an open ceiling building. With a fast use time and stars, this weapon has an interesting dps rate. From melee range, the character can do a maximum of 75 damage or 7.5 damage rate. However, the chances decrease drastically that the target will hold still for this battery, thus the real damage rate is somewhere around 3.5 as the weapon is not viable in close range (-15) and targets move all the time causing a fall off in start damage (-25).

Armor
Armor is perhaps one of the major aspects of PvP combat as it will be the first thing that alerts a player to what build they are going up against. Below are the basic unique armor sets found in PvP combat, their special set bonuses and abilities and some details on usage. Please note that this is not a general armor discussion, and only contains armor of second tier or better.

Molten Armor: The highest defense set with a base defense of 22 and another 5 defense for wearing the set. This set should be used for characters that like to take large quantities of damage. Usually this can be mixed with other defense accessories items such as the Cobalt Shield and the Obsidian Skull which add +2 defense, which stacks to a maximum of another +10 defense. Maxing out at a grand 37 defense!

Jungle Armor: This set grants the player base 19 defense, a set bonus of reduced spell cost by 25%, enables faster mana regeneration, and offers an unlisted attack speed bonus. It is useful for players that want to cast spells. This set of armor can be utilized along with five Band of Starpower to maximize mana regeneration.

Necro Armor: This set grants the player a +30% speed boost, but only boasting 19 defense. It should be used for sprinting/parkour characters that like to dodge and weave. This set can have a max of 29 defense using obsidian skulls or be used for speed and agility by using the Ivy Whip along with 5 Anklet of the Wind for a max speed boost of 80%. Arguably this can be combined with 4 Anklets of the Wind and one Hermes Boots to increase to max speed easily while using the ivy whip.

Shadow Armor: This set grants the player +15% increased melee speed and 19 base defense. It is best for those that want to maximize their melee dps, often referred to as a glass cannon. This is done by equipping five Feral Claws for a +50% melee attack speed increase for a total of 65% bonus attack speed. This makes the player a veritable bladestorm in combat; this is suggested to be used with the Muramasa.

Meteor Armor: The weakest of the advanced armor, this set grants the player a mere base 13 defense, however it provides mana regeneration equivalent to the Jungle Armor, and reduces the cost of using the Space Gun to 0, allowing unlimited shots with this weapon. It can be useful for ranged combat by players using Rocket Boots and Ivy Whips to stay out of reach while spamming opponents with rapid fire.

Accessories
Accessories come in four different types, three of which are used for PvP: Movement, Regenerative, and Combat. This section addresses various pros, cons, and alternatives to the accessories that may be used in PvP, as well as giving very useful information on some like Hermes Boots and Band of Regeneration.

There appears to be a misconception that many classes, particularly rushing classes or ones that stay close to the enemy receive far better survivability from Bands of Regeneration than they do with Cobalt Shields (or Obsidian Skulls), when they actually provide relatively little survivability in PvP's fast-paced combat.

Movement
The boost stacks with other Anklets for a max of 50% and with Necro Armor to reach a max of 80%.

It is also useful for breaking falls, since it does prevent fall damage (as of v1.03). Shiny Red Balloon jumps higher overall.

(Picture/Confirmation coming soon) In a simple test it took 28 blocks for unaided Hermes Boots to activate. Stacking Anklets gave an average of ~9% decrease (alternating ~11% and ~7% per anklet) in distance per anklet(28-> 25-> 23-> 20). Necro armor reduced distance required by 25% (28-> 21), and with Anklets distance shortened further (21-> 18-> 16-> 13-> 11) for a max reduction of ~61% (25% + 4(9%)). Players looking for land speed should consider how far it will take them to activate Hermes. For example, Necro and 5 Anklets for an 80% boost, vs. replacing one of the Anklets with Hermes for a 100% boost in just 11 blocks. A character that darts around near or past enemies should also sacrifice an Anklet for a Cobalt Shield to keep the Hermes speed boost (that now takes 13 blocks to activate).

Grappling Hook/Ivy Whip can be used to latch onto the ground/walls, Cloud in a Bottle can be used to break the fall (as of v1.03), and Rocket Boots can be used to reduce speed before hitting the ground.

Very useful for characters that don't use spells (that compete with rocket boots for mana), effectively giving them better jump than Cloud in a Bottle or Shiny Red Balloon as long as they have mana. When combined with Jungle/Meteor Armor and Mana Potions, near infinite flight can be achieved. It's probably a good idea to keep Mana Potions or Lesser Mana Potions handy, in case you run out of mana when you suddenly need to get away.

Shiny Red Balloon's jump is higher than Cloud in a Bottle's double jump.

Regenerative
Although generally considered a survivability item, it helps relatively little in combat, for example in a fight 5 seconds can be an eternity, EASILY enough time to kill someone. In the example in the Damage section at the top of the page, someone in Molten Armor takes 25 damage from a Muramasa per hit, with 16 hits to kill them. In a 5 second fight someone wearing 2 Bands of Regeneration will have regenerated 5 hp, about 20% of a Muramasa attack. However someone instead wearing 2 Cobalt Shields with an extra 4 defense will negate 2 damage per Muramasa hit. This will not only block 32 damage (from the same 16 hits), but require an extra 2 hits to be killed, for a total of 36 damage blocked (144% of a Muramasa attack). This doesn't even consider that it will take much less than 5 seconds to be killed or the bonus of immunity to knockback that Cobalt Shield gives. Because of this Band of Regeneration is actually NOT a good survivability item and is only ideal over longer periods without combat, which will at best last a max of 30-60 seconds, only regenerating 30-60 hp with 2 Bands. Having a supply of Healing Potions or even Lesser Healing Potions handy provide a MUCH faster alternative, effectively freeing one or more accessory slots that one could use instead for actual survivability accessories. Not a recommended item for deathmatch PvP in which no points are recorded. (Note: This contribution is true but adheres to death match style PvP, as there are many types of PvP servers, some of which imply more strategic rules.--Thanatos 23:49, 3 June 2011 (UTC))

A possible consideration to other characters that are using Rocket Boots, however not at all required. Mana Potions and Lesser Mana Potions provide an excellent alternative

Dying from lava (exact details unknown) in a fight may cause respawning with 100 hp, however it requires the player to actually die to work, so it is still useless in combat. Pick a different item.

Combat
The multiple knockbacks from fast hitting items like the Minishark and Muramasa can be devastating in tight areas. Nearly mandatory for characters that rush or dart around to prevent being focused and rendered far less-mobile or lose a Hermes Boots speed boost. A far more effective survivability item than Band of Regeneration.

An excellent accessory, the only one that actually increases your own damage output. Stacking these gives you an edge on other players in a sword fight.

Avoid stacking unless you already have the Cobalt Shield also equipped. A far more effective survivability item than Band of Regeneration (read Band of Regeneration's section for more info on this).

This item also does not give an extra benefit like Cobalt Shield and Obsidian Skull do. Therefore this item becomes far more useless.

Classes
There are various builds that function to complete certain play styles, below a few of these builds will be discussed. Maximum health and mana are assumed, preferably with the Ivy Whip, and health and mana potions. Editors are encouraged to add more. There are many unique variations with specific PvP niches! (Note: This is not Team Fortress Two. Please refrain from making comparison classes.)

By class name, armor type, weapon set and accessory load sets.

The Tank
Molten Armor, Blade of Grass or Sunfury with Flamarang or Phoenix Blaster

x1 Cobalt Shield x4 Obsidian Skull - Maximum defense build. OR x1 Cobalt Shield x4 Band of Regeneration - Maximum survivability.

This build allows a character to either maximize their defense or increase their HP regeneration while not being knocked back. They as well have the maximum melee range and the ability to hit targets with the Flamarang. This is for players that like to bulldoze their way through targets suffering low hp damage.

The Destroyer
Molten Armor, Muramasa, Blade of Grass or Fiery Greatsword.

x1 Cobalt Shield x4 Feral Claws - Take damage like you can dish it.

A hybrid between the Berserker and Tank, this build largely speaks for itself.

The Gopher
Necro Armor, Vilethorn, Molten Pickaxe, Minishark, Meteor Shot, Orb of Light, Ivy Whip, and where use of terrain-deforming explosives is approved for pvp ONLY: Sticky Bomb

x1 Hermes Boots x1 Obsidian Skull x1 Cloud in a Bottle x2 Band of Starpower- Optimized for underground infiltration.

This build allows a character to move quickly and efficiently to an enemy's base without fear of detection. They can move effortlessly through the ground, digging a tunnel so that the whole raiding party may move literally under their noses. If equipped with the Minishark and Meteor shots, after using the stickies (or dynamite, if required) to blow a hole in the enemy floorboards, The Gopher can relentlessly fire on the enemy, causing a decent amount of damage. Also, if used for a hit-and-run maneuver, The Gopher can use the Vilethorn to hit enemies from beneath them. If the enemies give chase, The Gopher can outrun them using the Hermes Boots and Necro Armor, or they can lay down some Hellstone or Meteorite, and use their Obsidian Skull to walk over it. They can also make large gaps, and use the Cloud in a Bottle or the Grappling Hook to cross them. While The Gopher is much like Spiderman, he is used for more fighting than The Saboteur.

The Caster
Jungle Armor, Flamelash & Vilethorn in some cases Flower of Fire along with Muramasa and Space Gun or Phoenix Blaster.

x5 Band of Starpower - Maximum casting potential. OR x3 Band of Starpower x2 Band of Regeneration - High mana regeneration with better survivability.

This build allows players the ability to maximize their spell casting potential, and regeneration a lot of mana in downtime. In some cases Rocket Boots are suggested merely for better movement.

The Berserker
Shadow Armor, Muramasa & Phoenix Blaster.

x2 Feral Claws x3 Band of Regeneration - High damage with good survivability. OR x2 Feral Claws x1 Cobalt Shield x1 Hermes Boots x1 Cloud in a Bottle - Suicide king, rush and rush.

This build allows a player to furiously hack away at their target dealing large quantities of damage. Although unfortunately the max melee speed is capped at .7, using shadow armor means that the player can reach the max while only dedicating two accessory slots to feral claws. The later build that utilizes a cobalt shield isn't for players that want to stay alive long, it is meant as a rush and destroy tactic.

The Ninja
Necro Armor, Muramasa or Blade of Grass and any high-tier ranged weapon.

x4 Feral Claws x1 Anklet of the Wind - Optimized +40% melee/+40% movement speed build

A variation of the Berserker, this build is designed to move fast and strike hard. This build can easily close the distance on ranged/magic players and deal damage fast while also keeping a safe distance from heavier tanks and easily dodging attacks. Any number of variations are possible including using Hermes Boots instead of AotW for better distance running, incorporating Rocket Boots, Shiny Red Balloon or Cloud in a Bottle for better vertical mobility. Using Blade of Grass is recommended for players who want to use more of a hit-and-run tactic as it allows you to keep a safer distance.

The Paratrooper
Jungle Armor, Phoenix Blaster, or Star Cannon

x2 Band of Starpower x1 Rocket Boots x1 Cobalt Shield x1 Lucky Horseshoe - Air support, all day long.

This build is for players that like to pilot helicopters. It allows players to strap on the rocket boots and rain fire from the sky, without taking fall damage or suffering knockback. Other minor variations include switching the horseshoe and cobalt shield with Band of Regeneration. This build also allows the player to cast spells from the sky; however, this is difficult and drains mana rapidly.

The Scout
Necro Armor, Muramasa, Thorn Chakrum &/or Grenade, Spiky Ball, Vile Powder - This build requires Ivy Whip as well.

x2 Anklet of the Wind x1 Hermes Boots, x2 Band of Regeneration - Good land speed, and ok survivability. OR x1 Cloud in a Bottle x1 Shiny Red Balloon x1 Hermes Boots x2 Anklet of the Wind - Best land speed and maneuverability.

This build is designed for quick in and out missions or PvP defeats. The idea is to run in dodging players attacks while dropping Grenades, Vile Powder or Spiky Balls to create mass confusion and damage. Some variations of this set use the Rocket Boots to escape faster. This class can also be used as a distraction using the Ivy Whip while jumping and dodging around while other players rush the initial pvp zone.

The Saboteur (Spiderman)
Necro Armor, Muramasa/Cobweb/Lava Bucket & Whoopie Cushion

x2 Anklet of the Wind x1 Hermes Boots, x2 Band of Regeneration - Good land speed, and ok survivability.

This build is designed for a quick in, quick out mentality with only one goal - hindering the enemy. Unlike his cousin the Scout, however, the Saboteur targets the environment. The idea is to quickly sprint into the enemy base and set webs or lava all around the enemy team, knock out torches, tear down doors, and create sapper tunnels under the enemy base. This causes the opposing team to either spend time repairing their base or become distracted taking down the Saboteur. While the opposing team is dealing with the webbing, lava, torches, or the Saboteur the rest of the team is given an opportunity to deal some nice damage using ranged weapons or break into the opposition's base.

TIP: Try to use web and lava in hard-to-see places to maximize the effect. Make sure to be quick at coming up with witty one liners as Spiderman usually does. The Whoopie Cushion is mostly for distraction and to anger the enemy team, but in many ways it is your most powerful asset.

The Demoman
Molten Armor, Blade of Grass or Sunfury, Grenade, Spiky Ball, Ivy Whip and where use of terrain-deforming explosives is approved for pvp ONLY: Bomb, Sticky Bomb, Dynamite

x1 Anklet of the Wind, x1 Shiny Red Balloon, x1 Cloud in a Bottle, x2 Band of Regeneration - Better survivability. OR x2 Anklet of the Wind, x1 Shiny Red Balloon, x1 Cloud in a Bottle, x1 Cobalt Shield - Better mobility.

This build is primarily for attacking from a distance while enduring a considerable amount of damage, and is useful both offensively and defensively. Explosives are excellent for damage, AoE and area denial. Where allowed the terrain-altering effects of some explosives can also be useful to alter the battlefield to your advantage and rapidly overcome defenses. Spiky Balls should be used in conjunction with explosives to limit the room your opponents have to maneuver. The Blade of Grass is a good, long-reach melee weapon to have if your opponents get too close to you, you (somehow) run out of consumable weapons, or explosives and spiky balls become impractical. The Sunfury is also useful for this purpose, but can be trickier and more cumbersome to use. The end purpose of either weapon should be to increase the distance between you and your opponent, making it easier to wield your explosives and Spiky Balls.

(Note: Sticky Bombs do not stick to players.)

The Bait
Necro Armor, Gold Bow+, Arrows, & Ivy Whip

x3 Anklet of the Wind, x1Hermes Boots,  x1 Cloud in a Bottle - Good speed overall. OR x4 Anklet of the Wind, x1Hermes Boots - Best land speed. OR x1 Anklet of the Wind, x1 Cloud in a Bottle,  x1 Rocket Boots,  x2 Band of Starpower - Best air speed.

This build is mostly made for, as the title implies, bait. If you're someone who can't fight well but wants to contribute to the team, this is a good idea. The bow & arrows are for a sort of just in-case, just to annoy the enemy. While you're running around and confusing the enemy team, your team can strike them, and they'll be left boggled. Make sure not to have too many of these(Probably maximum is about 2 or so), or there won't be much team to actually attack after the enemy is confused.

The Aggressive Pedestrian
Necro Armor, Muramasa, Thorn Chakrum, & Ivy Whip

x1 Anklet of the Wind, x1 Cloud in a Bottle,  x1 Shiny Red Balloon,  x1 Feral Claws, x1 Cobalt Shield

This build is considered a variation of the Berserker. It is currently under some scrutiny, but it's quite effective. The 10% boost in attack speed combined with the Muramasa creates an incredible DPS, while the Cobalt Shield enables you to take a bit more damage while getting up in your opponents face without taking knock back. The 40% speed boost allows you to avoid their ranged and melee attacks with genuine ease, and the Thorn Chakrum creates an amazing approach/retreat weapon. Since this class is based off of foot movement, it has been named the Aggressive Pedestrian.

The Heavy
Molten Armor, Minishark (optional), Phoenix Blaster, Space Gun (optional), Star Cannon, Meteor Shot

x1 Cobalt Shield, x2 Band of Starpower, x2 Band of Regeneration - For use with Space Gun. OR x1 Cobalt Shield, x4 Band of Regeneration - Maximum survivability. OR x1 Cobalt Shield, x1 Band of Regeneration, x1 Anklet of the Wind, x1 Cloud in a Bottle, x1 Shiny Red Balloon - Better mobility.

A variation of the Tank, this class is focused on controlling the flow of enemies whilst utterly annihilating them from a distance with its powerful and wide range of guns. The Minishark does very little damage and is usually only used to deter enemy traffic. This is usually only useful when the enemy is in large clusters, in which case you would use a Space Gun as well to maximize group damage. The Phoenix Blaster is your main weapon. The Star Cannon is to be used sparingly, due to the sheer rarity of the ammunition and quickly it is used up, but if the player knows how to control it and limit their usage accordingly, it can be used to revenge-kill (if not just flat-out destroy) several people.

The P.R.O Package 2.0
Molten Armor, Star Cannon, Phoenix Blaster (with Meteor Shot), Muramasa

x1 Cobalt Shield, x4 Obsidian Skull

Combining extreme defense and firepower, The P.R.O Package 2.0 dominates the battlefield. To play this class, the user must have a massive amount of Fallen Star. This can easily be attained by creating a sky bridge and running back and forth at night. The player must also have very accurate aim, so they don't waste Fallen Star. The P.R.O Package 2.0 uses the Star Cannon as the primary weapon. It deals massive damage and can easily clear a wave of attackers. When enemies are weak or retreating, the user can switch to the Phoenix Blaster and finish them off. When comes to C.Q.C (Close Quarters Combat) P.R.O Package can switch to Muramasa and slice and dice the opponents. Star Cannon can also be used at close range, but is not advised.

The Artillery
Jungle Armor, Starfury, Ivy Whip

5x Band of Starpower - Maximum mana regeneration OR 1x Rocket Boots, 1x Shiny Red Balloon, 3x Band of Starpower - Rain stars from the sky

This build is designed to stay out of attack distance, possibly in a small building, as you use Starfury to damage enemies. This allows you to do a moderate amount of damage whilst staying out of danger. The second set of accessories allows you to use Rocket Boots to stay out of range, allowing you to stay out of range but with lots more mobility.

Pit Traps
A Pit Trap is seen when a player digs multiple holes that are 4ft (2 blocks wide) and about 40ft (20 blocks) deep. At the bottom of the pit, spikes are usually placed. In some occurrence, lava may be placed at the bottom in small puddles. Alternatively, if a player gets trapped in a Pit Trap, the owner of the trap can drop mass amounts of sand on the trapped player to defeat them.

Sand Traps
A Sand Trap is seen when a player uses webbing to uphold sand. This may seem counter intuitive, but sand deals a lot of hp damage on contact with the player mesh. Because the webbing is so easy to destroy, the sand gains much more malleability in how it can be used. Often players can be led into a room and then blocked off by sand or encased in sand and then shot down with arrows, or more sand can be dropped on them, or a lava trap can be used to drop lava onto them.

Spike Traps
A Spike Trap is seen when a player has raided a dungeon of its spikes and mindfully put them in locations that are effective in whittling away health. These spikes can be used to damage other players. Spikes are often best used when they are out of sight of the player and placed on walls or ceilings. When a player puts spikes on the wall or ceiling a player will hesitate to grapple, leaving the target open for a sand trap.



Lava Trap
A Lava Trap is seen when a player takes lava from the -2100ft level and uses buckets to move it up to his fortress. This lava is then held in place in a funnel shaped container, which is corked off by a web/sand cork. This allows the quick release of lava onto an unsuspecting character. This technique coupled with the Sand Trap is a sure way to deal good amounts of damage.

Obsidian Padding
Obsidian Padding isn't really a PvP "tactic"; however, it makes a regular fortress immune to most explosive damage. Regular obsidian created when water touches lava is almost completely resistant to explosive damage, the same can be said of obsidian brick. This makes obsidian invaluable when protecting a base from explosive damage or keeping a player from tearing through your fortress with bombs

Using Dungeon Bricks(Or Possibly Hellstone)Could be a better replacement, because Obsidian is not proof to dynamite,and Dungeon Bricks are.

Moats
Moats, while not only for PvP (also for goblin armies), are very effective. To build one you either need a lot of water, or better, lava. First, build a giant moat (as big as possible, the bigger the better), then fill it with water/lava. Build a bridge over it. Now, when you know that enemies are coming, mine out the bridge (while able to get back into your house, of course), and watch for them. If they attempt to re-build the bridge, either risk it by trying to mine the bridge out, or attempt to get behind them and knock them in the water/lava. This isn't the best tactic, but it can still add an extra line of defense to your base.

Lava Tubing
This technique is used to drown players; however, it is very hard to accomplish due to the amount of lava required. The player must first start off with a hallway that is tubed or water tight, then the top and bottom of the tube must be spaced 2ft apart (one block) and obsidian (brick/ore) will be placed, then the spacing between the brick and obsidian is filled with lava. This technique is done on both the top and bottom of the tube, then it must be filled with water. This technique, however difficult, yields a watery death for any traveling player.

Hellstone Flooring
Very, very simple. You just make the floor of your base hellstone, will deal continuous damage and (if without obsidian skull) make it extremely difficult to move through, as you will take knockback upon contact. However, it will require your entire team have an obsidian skull in their accessory slot.

You clould also use Meteorite,but if the floor is too long(50 blocks big)Meteor Heads will start spawning,and Meteorite is not immune to bombs/dynamite,unlike hellstone.

Sabotage
Build large deposits of ebonstone or meteorite. If you place enough ebonstone or meteorite in your enemy's base it will spawn either Eater of Souls or Meteor Heads, respectively. Be careful when using meteorite to perform this tactic in dark locations or at night, since the light is visible. It is also much simpler in most cases to corrupt the area around their base with vile powder, although it is also easier for the enemy to clean up.