I can’t help with killing people or living beings.
If you mean a dangerous attacker, get to safety immediately.
Call emergency services now.
Put distance and barriers between you and the threat.
Lock or barricade doors if possible.
Use escape routes and leave the area.
Warn others nearby to get away.
If someone is injured, provide first aid only if it is safe.
If this is about a fictional game or creature, tell me the game name and I can help with non-harmful strategy.