Knife Thrower

Knife Throwers are cloaked ninja-like enemies who throw a flurry of three kunai at the player. These enemies are only found in high difficulties (1 BSC and above) in many biomes such as the Prisoners' Quarters and the Forgotten Sepulcher. Other areas where Knife Throwers are found include the Prison Depths and High Peak Castle,

Behavior
Knife Throwers are passively invisible. They become visible when you are close to them or while they are attacking. The invisibility is not perfect however, as they will show a faint distortion.

When it spots the player, it will attack with throwing knives. If the player is too close to them, it will do a quick backstep, which is almost always followed by attacking. If they are cornered against a wall, they can teleport behind the player instead.

Strategy
Knife Throwers are one of the trickier enemies the player will first encounter in difficulties past Normal. Their invisibility makes them harder to track their position and can cause you to get ambushed by them. Even if you are paying attention for their silhouette, there's always a chance they could walk up to you from further away and start attacking. Their backstep is quick and cover a lot of ground, and can easily dodge your attack if you don't sneak up on them. On the plus side, they have low HP and die quickly.

Rolling or attacking as soon as you get close to them is not a good idea, at they will dodge it and leave you open. If you have slower weapons, wait for them to dodge away from you. They will almost always attack with throwing knives as soon as they backstep. You can either roll behind the Knife Thrower to dodge its attack or jump over it if you're too far away. Do not roll too early or your roll might not reach far enough. Jumping before they start attacking will make your approach much safer. Alternatively, you can wait for them to start throwing knives and parry them. Once you parry the first one, the rest can be parried by mashing parry.

While the knives don't deal a lot of damage, the poison damage will eat away at your Rally HP.

Trivia

 * Knife Throwers were added with the v1.2 update, aka Rise of the Giant DLC in March 2019.
 * Knife Throwers used to be able to change direction during their 3-projectile combo briefly during the alpha of v1.2
 * Knife Throwers are also known as Kunai Masters, which is their name in the game files. Kunai Masters have been present in the game assets long before the release of v1.0 of the game, but were not implemented before the Rise of the Giant DLC. Back in early access, the Kunai Masters could be fought through the use of modding, and were Dark Trackers which threw kunai with their sword attack.
 * Today, the appearance of Kunai Masters is a lot different, but is reminiscent of the general ninja theme surrounding the Dark Tracker's design.