Test it :)
So why should you play Ragnaros, the Firelord? Ragnaros feels almost like a Multiclass Hero except that he is both an Assassin and a Specialist at the same time. He can deal tons of damage, even from afar, to multiple enemies but also take over a Fort or Keep to prevent all damage to it for the duration while also becoming an improved form of himself. Lava Wave and Molten Core can stop enemy pushes quickly and Empower Sulfuras and Living Meteor can shred multiple enemies at once. He is almost the best of both roles. However he does lack survivability, and while the healing from Empower Sulfuras helps he needs to be fighting for the healing to happen. This downside does not detract from Ragnaros's viability though, as Supports usually cover these weaknesses and Warriors can take the brunt of the damage. So if you want to play a high damage dealing Assassin with Specialist-like push control, then Ragnaros is the perfect pick for you!