This card is... STRONG!

The card reads: "Forced: After Hummerhorns engages you, deal 5 damage to a single hero you control."

Does it's Forced ability triggers if you optionally engaged it?

If so... How do you beat it solo? Not gathering threat and dealing damage through Gandalf and Dúnhere?

The Forced goes off either way:

Rules, Page 16: "Whether an enemy is engaged through an engagement check, through a card effect, or through a player’s choice, the end result is the same, with the enemy and the player engaging one another. In all cases, the player is considered to have engaged the enemy and the enemy is considered to have engaged the player."

And yeah, finding a way to kill them in the Staging Area is probably your best bet.

Yes is powerful but you look on that from another perspective. If you have Gimly with armor in play you like to engage hummerhorns to get damage on Gimly and make him stronger.

Then yes there is a lot of ways to kill them on the staging area by direct damage or Dunhere by one strike.

what if i used Quick strike from the tactics deck while he is still in the staging area.. would that be valid, since i would be attacking first.

Just with Dunhere, as the card directs you to declare an attack "against any eligible enemy target". The staging area isn't eligible for all other characters.

most multiplayer games should be running frodo somwhere I think, then you always have an out to hero destroying cards.... though I am not sure that the new troll can be gotten around with frodo

another way that hasnt been mention is infighting.....though this has the obvious downside of healing one enemy