Goldvein Hydra is an excellent X cost creature for most of the Gx archetypes that is cool and makes treasure. Voracious Hydra was originally going to be the cut, but Primal Might sees so little play that I think more creatures would be better.

Gideon Blackblade is a card I personally enjoy but he’s not very interesting and he’s not very good. Aven Interrupter is a very powerful disruptive creature that serves as a Remand on a stick. The bird is hella good, sorry Gideon.