Ive not seen a skill which does this anywhere on guildwiki.
I suggest they add a skill to cause spirits and minions, cast by the enemy to expire faster. Something like;
"Spirits and minions summoned by enemies, will expire 10-50% sooner. This spirit will die after 30-200 seconds."
I suggest this because when playing pvp challenges like FA in factions, MMs add a huge advantage to the team with one.
Ideas?
[edit to my original description]
Due to a few suggestions, such as minions can be healed, im re-wording it...
"Summoned spirits and minions within range expire #% sooner, and minions within range cannot be healed. This spirit will die after #seconds".
f

It still would look good with all the other skills I have.