To use Strangle, you must first purchase it at the start of a round. It costs 2000$ and uses 2 essence. It is mainly a defensive magic, useful to fill up a passage with spikes to prevent enemies from reaching the flag. It doesn't deal much damage, so getting a kill with it might prove to be difficult. One way to get this is to try and trap a player in strangle in a closed area, and then damage the enemy that is trapped in strangle. A few headshots (but not too much) will help. If you kill the player with a bullet, it won't count as a Strangle kill. Also, don't use it on dwarves, since they will suck up the energy from Strangle and use it as magic.