Slammer

Slammers are big blue birds with five eyes and pink darts embedded in their back. They are found in the Corrupted Prison, Cavern and Astrolab.

Behavior
When Slammers detect the player, they will proceed to get within range by jumping and pursue them relentlessly until they are slain. Their only attack involves them slamming their ground and generating ice spikes.

Slammers are immune to most stun effects such as the, but not against breach-based stun. Elite counterparts are faster but otherwise similar to the regular ones.

Strategy
Slammers are one of the most dangerous enemies in the game. They have exceptional DPS, health, attack rate, range & response times. Their only real weakness is that they are vulnerable while they are jumping between platforms. You can exploit this to get one free hit on them right when they land. Rooting them while their back is turned against you is the most effective way to kill a Slammer, which it can't do anything about. Burst damage and freeze skills are very useful to have in case you can't kill a Slammer fast enough.

Slammers can only target grounded threats and are otherwise entirely harmless. Take advantage of this and utilize nearby chains to your advantage.

If you do let a Slammer start attacking, stay on the air for as much as possible, especially while they are facing you. Get behind them as fast as possible and run to a different platform.

Slammers should be fought 1v1 whenever possible. If there are too many enemies around it, use the Homunculus Rune to draw aggro. Do not dive attack into it because they will not be stunned by it.

Trivia

 * Slammers were added with the v1.2 update, aka Rise of the Giant DLC in March 2019.
 * Slammers used to be giant bats according to a Rise of the Giant preview, possibly explaining their stun immunity via echolocation.
 * However, notes in Astrolab contradict this, stating that they are simply mutated crows.
 * Slammers lack feathers on their body and wings, probably explaining why they cannot fly. The tranquilizer darts and collar with a broken chain hint they may have been beasts of burden before the Malaise outbreak.