It's like an easy way of scripting without having to type in messy code. You can do just about anything with events, really.
He meant what to do in events for it.
The bots will already want to kill you in a minigame.
If you want to know how to do it on a bot that doesn't do that:
onBotSpawn > Bot > setTeam > Enemy
But if you want them to fight eachother too:
onBotSpawn > Bot > setTeam > Mercenary
You can probably figure out the rest of the teams yourself.
The following thing is an addon, can't remember where it is but you could probably search it.