I feel like Fungor definetly needs some love... Today I moved on past him and...
the fight was nowhere near challenging as for an expert boss... He got stuck when he hit a two block size tile wall... and got destroyed in seconds...
So not only it's underpowered at the moment, another feature that felt broken was that fungor's head doesn't count as him? I like headshotting enemies and it was weird that his whole head didn't feel damage (hitbox too small?)
Now I read on the wiki that you're planning on giving him better attacks, I feel like he needs a fairly huuuge buff. And give him a jump please. Double health and damage(Although that might be a little too much) would be fair imho. :/
I fought him with pre EoW gear.
P.S. I fought him a few times for all drops. Once he spawned like 100 blocks below me in a very small cave and got stuck there too, so he couldn't even hit me once... Because my (flying) summon pretty much ripped him apart by the time I digged down to him.