Hole io

This will come naturally with time, or you can specifically target it to get it done faster.

Killing an enemy requires you to be a bigger hole than them, and to then swallow them up by moving under them.

You will likely reach a size where this is possible against most enemies with about a minute left in the round. At that point, it's a good idea to nab a few kills here and there because enemy kills add to your size as well.

Once you kill 100 enemies in this way, the achievement will pop.

GLHF!