This card is insanely good. Makes Venom extremely versatile and should be a top priority card to acquire via mulligan. It's also the best way to manage his nemesis when combined with Run and Gun to clear the board of them using the second option.
This card also acts as Venom's signature ally even though he technically doesn't have one. Think of the Multi-Gun as a 3 cost 2ATK/2THW ally with a special ability to ping minions for one damage and doesn't take consequential damage when it does basic actions, but it can't block for you.