Nasty Ones involves playing cards (creatures, items or spells) with players attempting to reduce other players health to 0 (usually by attacking with their creatures). One of the key gameplay features is that whenever you lose Health Points you gain Nasty Points, which are used to play cards, allowing you to take revenge and potentially gain the upper hand after you have been hit with a heavy attack. Every card has a unique ability and games usually last less than an hour.

The rulebook can be found on the Discord server or Nasty Ones Website (which is a really cool place btw just saying). There's also this in depth video: