Volatile counter

Volatile counter was a counter with an innate ability: "Whenever a permanent with a volatile counter on it went to the graveyard from the battlefield, the volatile counter does 2 damage to target opponent". It was created by Mark Gottlieb for Aether Revolt, but later in the design process, it was put out due to complexity and flavor issues.

Volatile counters proved to be very interesting, mainly on creatures. You could put them on your own things to either discourage your opponent from destroying them or to sacrifice them and get in extra damage, or you could put them on your opponent's permanents to either discourage their use or create an extra bonus when you destroyed them.