Guide:Expert Mode

Expert mode is a world setting in Terraria that greatly increases difficulty, but improves item drop rates and offers a handful of unique boss drops. Enemies deal much more damage and have more health, debuffs last twice as long, and several bosses behave differently. It's recommended that you play Normal mode first to get a feel of the game.

The Beginning
When starting an Expert world, you should chop a couple of trees and craft a Wooden Bow to replace your shortsword, along with some Wooden Arrows. Expert mode enemies have higher knockback resistance, rendering melee attacks ineffective early on. A Spear from a Chest will prove useful due to its high knockback.

After that, start travelling along one direction of the world to scope out your new world and to find caves that will provide you with Ores and Chests to strengthen your equipment. Meanwhile, start building a basic house for the Guide, and other possible NPCs.

Earlygame, when presented with a choice between fighting or fleeing from an enemy, you should almost always flee (or surround it with blocks such as Dirt). Most of your upgrades will come from mining or looting chests, not from killing enemies. Engaging enemies like Hoplites that can kill you in two hits is rarely worth the risk.

Getting higher defense early on can be advantageous. An easy way to gain a little extra defense before you fill up on useful accessories is to craft Strings (30 Cobwebs each) until you receive one with the "Warding" Modifier (+4 defense).

Before you gear up, the NPCs are better at fighting than you. You can use this to your advantage by building houses with 2-block high gaps that they can shoot through. Another way to protect your base is to build a monster pit. It should be at least 5x7 with a block overhang on each side. The overhangs prevent monsters from jumping out.

You may also want to build your NPC base now, as several useful NPCs can move in, notably the Merchant.

Mining and Resource-Gathering
Mining in Expert mode is similar to mining in Normal mode, but with an emphasis on avoiding enemies rather than killing them. If combat absolutely cannot be avoided, it is advised to use bows, thrown weapons, yoyos, the Snowball Cannon, or anything that attacks from a distance.

Avoid stepping on Pressure Plates at all costs. Even a Dart Trap can deal more than 100 damage in one hit when combined with poison damage.

It is also recommended to get a Grappling Hook as soon as you can. Not only are they good for navigating terrain and avoiding enemies, but they can also be used for mobility in boss fights. The easiest way to get one earlygame is to purchase the Squirrel Hook from the Zoologist. If you come across a spider biome, you may want to take a look around before leaving (although dangerous). Doing this gives you a high likelihood of finding a webbed chest. Most likely, webbed chests have a Web Slinger in them, which can help a lot early game. Another type of grappling hook is the Gem hook. Gem hooks can be crafted from 15 of any Gem. Otherwise, a Hook can be slowly farmed by placing a Skeleton, Piranha, or Hoplite Statue over the wiring of a naturally-generated trap.

If you find a large amount of money, return to base and stash it. If you die far from your base, you have a high chance of losing any money you may have obtained (you drop 75% of coins on death instead of the usual 50%).

If you are having trouble finding ore or chests, a Spelunker Potion will be useful.

Fishing
Fishing provides several benefits to Expert mode players.
 * Fishing crates once Hardmode starts lets you obtain Hardmode ores without mining or even breaking Demon or Crimson Altars.
 * Fishing can get you the materials for a Sharkron Balloon which can be crafted into a Pink Horseshoe Balloon. A horseshoe balloon plus Lightning Boots or Bundle of Balloons can give players mobility similar to Hardmode Wings.


 * Fish can be cooked to get the Well Fed buff, which is the only way to get Normal mode-strength life regeneration.
 * Fishing for the angler guarantees you the Fuzzy Carrot, providing an early mount which can help with difficult boss fights, including the Wall of Flesh.
 * Fishing provides the ingredients for Endurance Potion and Wrath Potion or Rage Potion, powerful potions that make the game much easier.

Potions
Potions make all the difference in Expert mode. While it is possible to beat Normal mode fairly easily without potion use, Expert mode almost always requires potions. Some useful potions are:
 * Regeneration Potion, which increases regeneration by 2 HP/sec (requiring Bottled Water, Daybloom, and Mushroom)
 * Ironskin Potion, which defense by 8, essentially giving you a higher tier of armor (requiring Bottled Water, Daybloom and Iron Ore or Lead Ore)
 * Endurance Potion, which reduces all damage you take by 10% (requiring Bottled Water, Armored Cavefish and Blinkroot)
 * Wrath Potion or Rage Potion, which increase damage or critical hit chance by 10%, similar to using the next tier of equipment (requiring Bottled Water, Ebonkoi or Hemopiranha, and Deathweed)

For ranged users, the following are useful:
 * Archery Potion, buffing arrow damage and speed by 20% (especially good for the Daedalus Stormbow) (requiring Bottled Water, Daybloom, and a Lens)
 * Ammo Reservation Potion, giving you a 20% chance not to spend expensive ammo like Holy Arrows or Crystal Bullets (requiring Bottled Water, Double Cod, and Moonglow)

For mages, it is worthwhile to use:
 * Magic Power Potion, which increases magic damage by an astonishing 20% (requiring Bottled Water, Moonglow, Deathweed and a Fallen Star
 * Mana Regeneration Potion, which causes the player to regenerate as if they were standing still and near the end of normal regeneration (which is when mana regeneration is at its fastest (requiring Bottled Water, Moonglow, Daybloom, and Fallen Star).

Summoners can use:
 * Summoning Potion, which allows you to summon an extra minion (requiring Bottled Water, Variegated Lardfish, and Moonglow)

In hardmode, some good flasks are available to melee players:
 * Flask of Ichor, which causes your melee attacks to lower the enemy defenses (requiring Bottled Water and 2 Ichor)
 * Flask of Cursed Flames, which causes your melee attacks to inflict the Cursed Flame debuff (requiring Bottled Water and 2 Cursed Flame)

Potions are easier to make with the Alchemy Table, which has a chance to not use ingredients in the potions you make.

Preparing for the Bosses
Bosses are harder in Expert mode because they have more health and deal roughly double the damage, and sometimes they even have a third stage when normally they only have one or two, so be prepared.

Note: If you play Expert mode in Multiplayer, boss health increases further depending on the number of players.

At this point you would've obtained a few Heart Crystals and have 180 Health, if you find another Heart Crystal don't consume it because if you do, it will trigger the 1 in 3 chance of spawning the Eye of Cthulhu while unprepared, so keep that one until you have gear like these:
 * Gold/Platinum armor
 * Musket or The Undertaker
 * Ice Blade or with some luck, Enchanted Sword
 * Cloud in a Bottle (Tsunami, Blizzard or Sandstorm if you can get one)
 * Hermes Boots or its derivative accessories
 * A very well-made Arena will give you more chances to win.
 * Minecarts are very cheap against the Eye of Cthulhu, as you can then travel faster than the boss itself.
 * Food. If you do not have the Well Fed buff, your regeneration will be stunted in Expert mode.
 * All the combat potion buffs. Almost all combat potion buffs can be obtained Pre-Hardmode, and can prove to be quite beneficial.
 * Molten Armor, if possible (obtainable after acquiring the Reaver Shark). Expert mode bosses are difficult! Molten Armor can make the impossible fight doable.

King Slime
Fighting King Slime can be done easily and without armor if a proper arena is set up. To build an arena, place exactly 30 rope upwards and climb to the top. If done right, King Slime will not be able to reach you even when teleporting.

From there, you can slowly whittle down its health with a ranged attack until the fight is over.

Note: King Slime has a small chance of spawning in place of a regular slime on the outer 2/3s of the map. If you build the arena next to the ocean, you can optionally fish (as to not waste time) and wait for him to spawn, then run to the arena to fight him.

It is recommended to farm King Slime until you get a Slime Hook. This can make upcoming fights much easier.

Eye of Cthulhu
Eye of Cthulhu is much harder in Expert mode. It is recommended to have: The arena for the eye is relatively simple. First, flatten out the land at least 1 screen wide. (The longer, the better, but it doesn't need to be too long.) Then, put a row of platforms 7-10 blocks above the land. You can do more layers of platforms, but it is not completely necessary. Also, making Campfires and using Sunflowers help with the fight.
 * At least 160 Life
 * Lead armor or better
 * Food
 * A decent Hook
 * Shurikens/throwing knives (for the small eyes)
 * A metal bow with either Flaming or Frostburn Arrows
 * Hermes Boots or better
 * Cloud in a Bottle or other vertical movement accessories

In the first phase, the fight is relatively normal. Shoot the eye with your bow, and kill the servants with a piercing weapon. When the eye transitions into its next phase, it spawns a lot of servants, so it is recommended to clear them out quickly with a piercing weapon. When the Eye starts charging, run in one direction with the boots. If you get to the end of your arena, turn around. You can use the hook to accelerate yourself into the sprint.

As the Eye's health gets lower, it starts attacking more frequently, and the fight becomes a DPS race when its health is almost zero. Keep running, dodging, and shooting. It can help to have Grenades, as they explode on contact with the eye. Throw the grenades out so you can focus on dodging. Once he dies, you get a very useful movement accessory, the Shield of Cthulhu.

An alternate method is to use Minecart Tracks to make the fight easier. Make a minecart track at about 100 tracks, and hammer the ends twice. This will make your minecart bounce of the edge instead of losing all of its momentum. Use a Gold/Platinum Bow and then shoot at him with Frostburn/Flaming Arrows, but Frostburn is recommended over flaming because of the extra damage. You should also make a house for the Nurse close to the track and use Autopause to heal whenever you need.

Eater of Worlds
Eater of Worlds is a much harder boss in Expert Mode than in Normal Mode, but he also drops a very useful accessory: the Worm Scarf. However, its segments shoot vile spit, it travels/digs at a much steeper rate, and it has overall boosted damage and health.

A good technique is to try to make multiple bridges high enough so the Eater of Worlds can't reach you, similar to King Slime. Then just spam with your bow or one of these weapons:
 * A simple weapon of choice would be at least a Gold/Platinum Bow with Jester's Arrows. These arrows can pierce the segments to hit more than one at the right angle.
 * Avoid using Yoyos, they're great in general but not against worms like this.
 * Spiky Balls can be bought from the Goblin Tinkerer and they're still great in expert mode!
 * Put platforms along the ground to avoid uneven terrain and potentially any water that is in the caverns. Remember to place campfires.
 * If you broke 1-2 Orbs and let a meteor fall, the Meteor armor along with the Space Gun will work wonders to kill him.
 * Since the Eater of Worlds does not despawn once you die, you can place a spawn point using a bed at the beginning of the Corruption so you can spawn and continue to fight the Eater of Worlds. Make sure the housing is not corrupted or else it will not work. Also, try not to leave the corruption so the Eater of Worlds does not despawn.

Brain of Cthulhu
The Brain of Cthulhu has a few differences, most notably the ability to inflict several debuffs. The Creepers in the first phase may also inflict debuffs upon contact. In the second phase, it spawns decoys to try and confuse the player, and the decoys become less transparent as the boss's health depletes. Fighting the brain gives resources needed to make the Deathbringer Pickaxe, but his Expert mode item, the Brain of Confusion, is not very useful.
 * Spiky Balls can consistently damage the boss and its minions, no matter where it teleports.
 * A linear piercing weapon like the Space Gun or a bow with Jester's Arrows can quickly clear out the bunched-up Creepers.
 * A multi-leveled arena made of platforms to move up and down helps a lot for dodging.

Since the decoys move based on the relative position of the player to the brain, it is possible to figure out which is the real Brain by moving immediately when it teleports. The decoys move very rapidly to keep the player in the center, and the real Brain will only move at its regular pace. Otherwise, you can abuse autopause to identify the real Brain from its map icon.

Queen Bee
Queen Bee only has differences when it comes to speed and buffed stats. Still, it's important you exploit her nature, in different ways.
 * The stingers still can't pass through blocks.
 * She can still only shoot downwards.
 * The lower the health, the faster she shoots the stingers.
 * The lower the health, the faster she dashes.
 * The lower the health, the more bees she'll spawn at a faster rate.
 * Use Spiky Balls and travel in a circle, posing yourself on the opposite side of her. This will make her try to move above you, and as the bee is below you she'll get caught in the spiky balls.
 * The Bezoar negates the poison damage of the stingers.
 * If you don't like moving around in circles, you can build an arena where there's platforms in tall rows, with half the arena covered in solid blocks. Because the stingers can't pass through blocks, this is a probable choice to use.
 * If you aren't quite confident in your ability to dodge her rapid dashes near the end phase, you can use the Shield of Cthulhu to dash into her when she charges you, simultaneously negating the damage of her charge and dealing a small amount of damage to her. Watch out for stingers while you do this, as they can still deal their damage if she charges right after firing them.

Skeletron
Skeletron is one of the hardest bosses you'll fight in Expert Mode. The head's health is nearly doubled, the hands' health are nearly tripled, you have to defeat the hands before attacking the head, and once they're removed he shoots skulls that can be hard to avoid and have high damage. That said, here's a few tips:
 * Shield of Cthulhu, obtained after defeating Eye of Cthulhu, is a very useful accessory for mobility.
 * Try building an Arena that is both good for vertical and horizontal movements. It's easy to make the mistake of making a straight row of platforms, so make sure you have a tall arena as well.
 * Tracks and a Minecart can be very useful to avoid his hands and skulls, but be careful: if you build your tracks too long, Skeletron will despawn. Due to his high speed and acceleration, the best shape for track arena would be a circle or an ellipse.
 * If you want to challenge yourself and fight Skeletron before the Eye of Cthulhu, use a Hook with minecart tracks to hook to. With a nice hook, Sapphire Hook or better, the boots aren't even mandatory. However, it is highly suggested that you at least use the accessories as said above for Eye of Cthulhu.
 * The head when spinning must be avoided, as it can leave you trapped and it's game over. You can escape the trap by using a Slime Mount to jump out of it.
 * In the second phase, if you get used to the tempo of the skulls, you can cut through every few of them at the right time.
 * If fighting him for the first time, try moving around in a circle when he starts shooting the skulls. A featherfall potion and rocket boots are great for this, possibly even negating the need for a tall arena.
 * If you fight the Queen Bee before and obtain the Bee's Knees, it will make killing Skeletron nearly three times as fast. Drink an Archery Potion and he will be a piece of cake.
 * He only shoots his skulls if you are in line of sight. Hiding under a layer of dirt or other solid block and using a yoyo can whittle his health down, and then running away while he spins. If you can take care of the hands, this is a good way to fight him.

Wall of Flesh
The Wall of Flesh is another boss that will shred you in Expert Mode if you don't run away soon enough. Not only does it have buffed stats, but The Hungry respawn, so a piercing weapon is essential. Also, the lower the health, the faster he gets, which is like normal mode, except he can get fast enough to outrun your Hermes Boots. Here's a few tips:
 * A Demon Scythe with Jungle armor and Magic Power Potions will allow you to slaughter it off-screen by simply aiming in the direction of an eye and staying ahead with Movement Accessories.
 * Keep him off-screen, this will make the lasers easier to dodge and stop you from getting hit by the wall.
 * Beenades with a Hive Pack will end the fight in a mere minute. No strategy needed, just roll them out.
 * Phoenix Blaster with Meteor Shot is still a nice weapon of choice, due to the rapid damage and piercing properties.
 * Build a bridge covering at least half of your world for safety measures, and demolish any structures that are in your way. The fight is nearly impossible otherwise.
 * You can use Water Walking Potions to circumvent the need for a bridge.
 * You can also build a long railroad track to keep pace with the boss's speed.
 * Grenades and Molotov Cocktails can be used as they explode on impact. Dynamite is much less environmentally friendly, but results in an even faster kill.

Preparing for Hardmode
The main thing about preparing for Hardmode is making sure you have good items. It also helps to be organized and make a chest room, sorting items by category. The items you want include: In addition to gathering items, it is important to do other things such as:
 * Ivy Whip
 * Molten armor. Regardless of class, having the extra defense is really useful for early hardmode.
 * Magic Mirror
 * The Dungeon items (listed above)
 * Potion ingredients and seeds. (See also: Guide:Gardening)
 * Weapons with high base damage
 * Obtain maximum health and mana
 * Reforge weapons and accessories (Warding is recommended for going into hardmode)
 * Optionally, create quarantines. Quarantining existing evil biomes, sectioning off certain areas (your base, the jungle, and the oceans), and digging a hellevator all help maintain the spread of the evils.
 * Create a surface mushroom biome (for the Truffle)
 * Make an arena with campfires and Heart Lanterns (consider honey, the Nurse, heart and star statues)
 * Make extra NPC housing

The Dungeon
After fighting Skeletron, it is time to raid the dungeon. You want to get in and out as fast as possible, because there is a high chance of dying. The important things to get are: Feel free to gather as much as you can carry, but do not underestimate the difficulty of this area.
 * Alchemy Table
 * Bewitching Table
 * Cobalt Shield
 * Water Bolt
 * Shadow Key
 * Optionally, the Muramasa and Handgun (for the Terra Blade and Phoenix Blaster)
 * The Mechanic NPC
 * Some Water Candles

Hardmode
Once you have unlocked Hardmode, just like the start of the game, many enemies can once again kill you in a few hits. You'll need to find better armor and weapons.

Early items to go for

 * Just like normal mode, break demon or crimson altars to spawn valuable ores for armors. Since defense reduces damage more in Expert mode than in normal mode, armor is more important than ever.
 * For early melee weapons, yoyos are especially powerful. You can craft Chik or farm Amarok or Hel-Fire. The Dao of Pow is difficult to use, but strong.
 * For early ranged weapons, the Onyx Blaster provides strong damage.
 * For early magic weapons, you can craft spell tomes. Golden Shower is the best, followed by Cursed Flames and Crystal Storm. Sky Fracture is strong enough to last even through the mechanical bosses.
 * For early summoning weapons, you can farm Black Recluse's for a Queen Spider Staff and Spider Staff. Recluses are incredibly deadly in Expert mode, but you can use yoyos, the Imp Staff, wall-piercing spells or sentries like the Ballista sentry summons to slowly defeat them.

Preparing for the mechanical bosses
Many of the best items are in the Biome Mimics, especially the Daedalus Stormbow and Dart Rifle or Dart Pistol. Biome mimics are deadly. You can farm them by using a Key of Light or Key of Night, but make sure to have as good of equipment as you can, and to fight it in a prepared arena.

The Twins
The Twins aren't much of a difference in expert mode, they just move faster and have buffed stats as most bosses have. Still however, here's a few tips to help out dodging:
 * Spazmatism's cursed ball flames cause a lot of damage so it's important to dodge these for a safety measure. Simply move up and down at the right tempo to cut through the flames, and once he starts charging move to the side and fly away. Repeat process until he hits second form.
 * Retinazer is a difficult component because the laser attack is unpredictable. When he starts dashing it's at longer strides at slower rates comparing to Spazmatism, so watch out for the dashes.
 * Spazmatism's second form is simply faster and deadlier than on normal mode, so make sure you don't move in a straight line, shift up and down at opposite sides, reflecting off of the x-axis. In other words, move up when he dashes down, and move down when he dashes up. It will exploit the nature and make the fight 10x easier.
 * Retinazer's second form tends to be the most difficult part for most people on average. But if you move in a circle, you'll most likely be fine.
 * In general, like normal mode, make sure you kill one before getting the other in second form. (Spazmatism and then Retinazer is suggested)
 * Another way to kill the Twins for single players is to get the meteor staff, spider staff, and spider armor and hang out in the nurses house. Spawn the spiders in the house. When you are low on health, heal with the nurse. When the nurse is low on health, she will heal herself (And possibly YOU!). When one of The Twins charge at you, the spiders inside the house emit venom to that twin. When the twins are outside that house, use the meteor staff to attack. If you have damage boosting accessories, use them to your content. Make sure to have many mana potions (It doesn't matter what kind) and autopause ON.

The Destroyer
120,000 Health on The Destroyer sounds like a long road to drive on. But if you follow these tips, you'll pass the test with no problem:
 * Daedalus Stormbow is a very popular bow for a particular reason: It's super cheap. Use it with Holy Arrows and the boss will go down in seconds.
 * If you prefer Magic weapons, Medusa Head can damage each of The Destroyer's components, dealing 100-300 damage each hit. Using it can down The Destroyer in a few seconds.
 * Avoid touching the head at all costs, as it does nearly 300 damage on contact. If a hit is unavoidable, try to hit a body segment, as they do considerably less damage.
 * Long Swords are preferable, as The Destroyer is a Worm-boss type.


 * Make a small 5x5 room, with the middle block on the bottom of it be a platform. Then just stand inside and throw dynamites.
 * If you have the 5x5 room low enough so the Destroyer can go through it, you can use a sword like the Night's Edge to damage multiple segments of the Destroyer.


 * If you're still having trouble, ride in a minecart!
 * (These tips can also be used in normal mode)

Skeletron Prime
Skeletron Prime has the least difference out of the three mechanical bosses in expert mode, but here's a few tips anyways:
 * Destroy the Prime Laser first, then go for the head.
 * Make an Arena with platforms and not solid blocks, else the bombs will explode as you touch the solid ground on impact. The bombs are deadly so this is essential without tank gear.
 * A great weapon of choice is the Megashark or even better, Shadowflame Knife. Shadowflame Knife is the weapon of choice against only this boss, although you can still use it for the Twins. Because the Knives bounce around on impact, you can target the head and as they bounce off, they can still hit the arms. Also apply the Shadowflame debuff, so with Frost armor and a Fire Gauntlet, the debuffs will make him melt to pieces. (It should, however, be noted that his head is immune to Shadowflame, both head and arms cannot be set on fire, and on the the Fire Gauntlet cannot be obtained before defeating him anyway.)

Plantera
For many people, Plantera is the hardest boss to surpass without any cheesing. Here's a few tips:
 * Make a very tall arena with the platforms near the top, this will help the Spiky Balls she shoots out to be easier to dodge as they'll fall towards the bottom.
 * Make sure to not lead Plantera away from the Underground Jungle, as this will make it enter an enraged state where it's attacks and defense are boosted.
 * Teleporters can also be useful to move from one end of your arena to the other, especially during Plantera's second form, so that you don't get cornered by the tentacles.
 * Many projectiles can't go through blocks, so you can exploit this. You could use the chlorophyte spear to damage it through blocks.
 * An even cheaper trick than the one above is the Fetid Baghnakhs trick. Enclose in a tight space, use Titanium armor, Cross Necklace, and a bunch of buffs as well as offensive accessories, and you can kill Plantera in a mere few seconds. You don't even have to move one bit.

Golem
Golem barely has any difference in expert mode, just higher damage and health. Here's a few tips:
 * Destroy the hands first.
 * When the head starts shooting lasers, move back and forth above him in a "rainbow" formation.
 * Build a simple platform near the ground, around 15 blocks above. It'll make the fight just a bit easier.
 * Dart Pistol if you have a crimson world is superior to this boss, using Crystal Darts for the hands and head, then use Ichor Darts for the body.
 * Also, if you were lucky enough have a crimson world and obtain a Crimson Key, use Vampire Knives if you want to steamroll him.
 * If you have corruption, Scourge of the Corrupter is an absolute choice as well.
 * Above all, Megashark is still considerable, with Chlorophyte Bullets.
 * Suggested armor: Turtle Armor or above.

Duke Fishron
Duke Fishron is a fun boss to fight, especially in expert mode, with a new third stage at the end that will make your adrenaline go nuts. Here's a few tips:
 * Possessed Hatchet is the #1 weapon of choice, especially for melee class characters.
 * For a ranger, use the Tactical Shotgun with Chlorophyte Bullets.
 * For a mage, use the Spectre Staff or the Leaf Blower.
 * Tips for Sharknados, make sure that they spawn on each edge of the ocean, switching left and right. This is very easy in the first stage, but in the second stage, be careful!
 * For Duke Fishron, you can exploit his third form by jumping at a steady tempo, it may take a few tries but if you have a bottle equipped and you just jump up and down, falling/jumping RIGHT as he teleports each time, you'll be off the hook.

Moon Lord
A surefire way to defeat Moon Lord in Expert mode is via the Summoner kiting strategy, although it requires a bit of preparation.

It is essential that you dodge his phantasmal deathray, as it will kill you in seconds. Also, you should make sure that all his eyes die at a close time, so that the true eyes of Cthulhu don't overwhelm you.

Make sure you have Super Healing Potions.

General Tips
Expert mode doesn't just make you prepare more, it makes you more cautious with getting hit. You can actually get so good at dodging that a Worm Scarf or Band of Regeneration won't be needed at all. Here's a few tips:
 * Blizzard in a Bottle (or, even better, a Sandstorm in a Bottle) instead of Cloud in a Bottle make a tremendous difference in the long run.
 * Sandstorm in a Bottle will give you the opportunity for the Bundle of Balloons without even traveling in another world, an extremely useful accessory. Just get the other two bottles, and then fish up in the sky for the Sky Crates and get two Shiny Red Balloons, the third can be gotten from a floating island originally in your world.
 * The tips above include bottles because these accessories are essential for dodging, vertically. If you were fighting Duke Fishron, and he dashes towards you, if you were just wearing Wings, you'd most likely get hit. But if you had the Bundle of Balloons equipped, he would be a piece of cake.
 * If you don't know what accessories to replace with these bottles, replace the Cobalt Shield/Obsidian Shield or any other type of accessory that neglects knockback. This is a possibility because dodging is much more important, and if you never get hit, you'd never need the shield. Besides, the shield makes getting hit less annoying, while the bottles and balloons help you get hit less often. Easy to say which method is more useful.
 * Yoyos are a great addition to the game, and the name is shouted in Expert Mode. Amazon and Yelets are some of the cheapest ones to get. Amazon can be crafted for little materials right in the beginning of the game in the Jungle. Amarok can be gotten from any enemy by chance in the Ice biome in Hardmode. Yelets can be obtained from any enemy by chance in the Jungle biome after at least one Mechanical Boss is defeated in Hardmode.
 * Banners are much more important in Expert mode: with their effect doubled, they essentially revert the affected enemies to their Normal mode stats -- except your Defense is still buffed compared to Normal mode. Take care to hold on to all the banners you can obtain and hang them in the areas you frequent most often, and your life will be much easier.