Is Ditto useless?

I'd guess he'd be fine against Alakazam or Cloyster, since both got super low HP as well. So transforming into those you'd almost get the same thing.

Making an all Chansey / Ditto gym, because with Chansey typically one needs to bring their strongest attackers.

I think most people treat Ditto as a gimmick and a trophy. There used to be a lot of hype when it was released. Once you have one, it's fun to test once as a defender/attacker and then let them gather dust, but I've noticed that a lot of people keep these around in excessive amounts even though they seemingly have no purpose.

I'm also curious to see if anyone has found a use for their dittos. Using them as a defender seems rather pointless as they'll be at the bottom of a gym (even below Chansey) and using them as an attacker into a gym would only be desirable if the defender you battle has extremely low stamina (Alakazam, Cloyster etc).

As rumours are pointing towards genders being introduced, which in turn suggests breeding being introduced in the future, I am now regretting transferring all but one of my Dittos. Apparently, Ditto is useful for breeding in the other games.