Is Donphan underrated?

Donphan should have a similar CP to Espeon both maxed out are around 3k? I would stick to walking with Larvitar, Chansey, Snorlax, Dragonite, or Lapras especially since you have 53 candies already. I'm going to assume Phanpys aren't super rare for you.

IMO he looks like Rhydon but with a really weird and non-synergistic move pool, but with fewer weaknesses to kind of make up for it. I just don't know when you'd use him over someone else, because of the move pool. C/EQ might be good against Snorlax/Blissey?

Probably not a question of Donphan being underrated but rather his usefulness being ambiguous.

As a Defender his single ground typing renders him weak to water, ice and grass, and these types are ubiquitous.

As an Attacker his best moveset would appear to be Counter/EQ. EQ is a great move against poison, rock, steel, fire and electric, but Donphan has no STAB quick move and because of that, other double STAB mons would be clearer choices - eg, Rhydon (which has higher attack and HP stats anyway). So Donphan loses out in type-matchups.

Also if you're using Counter/EQ to take down Snorlax/Blissey, then Tyranitar, Dragonite and Machamp would serve better. Even Ursaring with double fighting moves is viable against Blissey/Snorlax.

So for me, Donphan's typing and moveset makes him hard to use in the game, there being superior options elsewhere.

He looks like a decent defender - high CP, sufficient STA and DEF, no double weakness. Counter deals decent damage on defense. He is kind of like a weaker version of Snorlax. We will probably see him quite often in gyms eventually. And he is probably going to turn out fun to fight against - there are many options, all equally valid, but none overpowering.

He is just missing anything to make people go all squeaky over. :-)

The main reason we won't see Donphan making a dent in the gym scene is named Vaporeon. Any pokemon with a lower max CP than Vaporeon will likely be knocked out too early of a high level gym. There's also the fact that every gym attacker these days often bring one or more Vaporeons to the fight, which makes any pokemon with a weakness to water a questionable defender anyway.

The problem with Donphan is the move pool and weakness to Vaporeon.

I managed to hatch a perfect Phanpy, evolved it and received Counter/PlayRough. Great against attacking dragonites but not great in defending a gym spot as its not Counter/earthquake.

I think he's one of the coolest looking mons and looks deadly in a gym.

Eventually I want a high level Donphan and will use him in gyms even if he might not be the best.

People put tons of 3000cp Ryhdons in gyms and they are as squishy as they get with double weakness to water. Might as well put something cool in the gym.

Check the aviable quick moves for donphan and you'll know why no one is talking about him.
None of donphan's quick moves have STAB and they're all pretty crappy.