[@Flamelord] The Demon Roses have corrosive powers, but still require contact to achieve that. Zac is pretty damn well equip to surround himself in holy fire that burns the physical corrosive powers to cinder while simultaneously destroying the magical corrosive powers.

If that doesn't work, he can literally turn himself into FIRE, and amp up his shields.

If that doesn't work, he can ask [s]plot[/s] Harley.

And then, being the only one there still alive, he could take his time getting the treasure. If the treasure is not on fire. Which is unlikely.