This is a relatively low ceiling event that is also easy to use. Just throw it on some Guild Sniper or Gunner that is well protected and that is immediately a good use for this card.  1 magic for +1 strength on a hard to kill unit is a big deal and a Hand Cannon will be key to making Vlox extra scary as he copies it.
One strategy is to use Hand Cannon on a Machinist, not to make the Machinist better (as it does nothing there), but to make Vlox really scary when copying that Machinist, especially if the Machinist also has Moto Boots.