Deerclops

Deerclops is a pre-Hardmode, encountered in the Snow biome at midnight during a Blizzard if at least one player in the world has either at least 9 defense or 200 health, or by summoning it using a Deer Thing in the Snow biome. It will not spawn naturally if there are NPCs too close to the player. Fighting the Deerclops is required for game progression, and defeating it rewards the player with coins and other useful items.

Behavior

 * The Deerclops has four attacks (five in Expert and Master):
 * If it is close to the player, the Deerclops will smash the ground, summoning a wave of ice spikes that quickly travels towards them. Every third consecutive wave does not go as far, instead spreading in both directions.
 * If it is not close enough to its target to use the ice spikes attack, the Deerclops will 'scoop' and then throw numerous chunks of debris into the air that fall back down. These chunks can pass through blocks.
 * The Deerclops will occasionally stand in place and roar, inflicting the Slow debuff on all players for 12 / /  seconds.
 * If the player is above the Deerclops for enough time, five shadow hands will be summoned around the player.
 * In Expert Mode, shadow hands will be periodically summoned that either move forwards slowly, move forwards quickly and curve, or spin in place. Shadow hands are summoned more frequently as the Deerclops' life gets lower.
 * The Deerclops cannot pass through solid blocks, but if the player is above it, far enough away, and the Deerclops cannot reach them, it will quickly rise through the blocks to reach the player.
 * If the player is more than 30 tiles away, the Deerclops will turn a dark shade purple, two reddish, semi transparent Deerclops' will begin spinning around it, and it becomes immune to all damage.
 * If all players are dead or there are none nearby when it spawned naturally, the Deerclops will wander around instead of immediately despawning. This will happen until a player gets close to the boss, at which point the fight will resume as normal. It will despawn after a few minutes have passed while players are not near or upon leaving and re-entering the world.
 * Like all other bosses, Pylons cannot be used while the Deerclops is alive in a world.

Tips

 * One may find it useful to bring a Warmth Potion or the Hand Warmer to the battle as the  Chilled and Frozen debuffs can easily kill the player if inflicted.
 * Building a platform of non-solid blocks about 6 blocks (twice the height of the player) up in the air, along with staircases made of solid blocks on either side to allow the Deerclops to get on, can elevate it high enough above the ground to prevent the boss from using its debris attack entirely, making the fight much easier.
 * Due to being able to inflict Slow from an almost unlimited range, accessories like the Anklet of the Wind or Magiluminescence alongside Swiftness Potions can help make the fight much more manageable.
 * Avoid lingering directly above the Deerclops, as the shadow hands it summons in this situation are very dangerous.
 * The player can run between the Deerclops' legs without taking damage. This is useful for avoiding the first two ice spike attacks, but the player should not stick around for the third.
 * Player should place their spawn point away from where Deerclops can wander, as Deerclops can stay around the spawn area.
 * This is especially recommended for Mediumcore players, as they can be left defenseless near Deerclops if they die in the middle of the fight.
 * Using the Shield of Cthulhu and a Blue Horseshoe Balloon or any of its variants, the player can simply jump over and dash when the Deerclops closes in on the player as the ice spikes summoned closer to Deerclops isn't that high. You may even opt to use platforms and a grappling hook's momentum if you don't want to risk being locked in place by hitting the Deerclops with your Shield's dash.
 * The ice spike attack is capable of interrupting a player's extending grappling hook, causing them to drop to the ground. Avoid moving over large gaps to prevent unnecessary damage.
 * The ice spikes deal less damage closer to the deerclops then they do further away. If the player has high enough defense, they can just pull a Wulfgang and brute force the deer clops down. A well fed buff and ironskin potion are great for this. Having a defense of 32 will result in taking next to no damage from the deerclops attacks at short range. A Campfire and regeneration potion should be able out-heal the deerclops dps easily on normal difficulty.

Trivia

 * The Deerclops is part of the Don't Starve Together crossover. Many of the items of this crossover are dropped by the Deerclops.
 * The Deerclops' purple invulnerable form in Terraria looks similar to its form in .
 * It is the only non-event boss in Terraria to not despawn after killing the player.
 * The Deerclops fight is one of two boss fights that consist of a single destructible entity, the other being the Empress of Light.
 * All other boss fights have either multiple bosses, multiple segments, or boss minions that play a part in their boss fights.
 * Between the versions 1.4.3 and 1.4.3.6, there was an NPC named  in the files which did not actually appear during the fight. It was invincible and had its own AI. It was removed in the 1.4.4 update.
 * The Deerclops is the first non-event crossover boss, as well as the first pre-Hardmode crossover boss.
 * It is one of seven bosses with exclusive boss music. The others include Queen Bee, Queen Slime, Plantera, Empress of Light, Duke Fishron, and Moon Lord.