What is the Goblin Mech's weakness?

When the Goblin Mech first enters on the throne room, he quite obviously spins around and shows that he has a coal furnace on his back. That makes me think this is a centerpiece in how to defeat him.

I haven't had a problem brute-forcing my way through the level by just piling damage on him, but I haven't tried on any difficulty higher than medium yet. I imagine I'll need to take advantage of his weakness on hard and insane if I plan on succeeding.

What is this boss's weakness?

1 Answer

According to the Dungeon Defenders wikia,

Like all bosses, the Goblin Mech has a weakness. By having one player distract the Goblin Mech, another player can attack it from behind. When the gate behind the Goblin Mech opens up, the Goblin Mech will take double damage.