Tentakook
From Inkipedia, the Splatoon wiki
Tenetooks are Octarians that appear in Splatoon 2. These enemies are extremely fast and leave behind a thin trail of ink. Tenetooks will take a key and speed away. The only chance players have to kill one of these is to corner it. Tenetooks can also throw splat bombs while they are being chased. https://www.youtube.com/watch?v=er_0RwY2Yxg
