UltiMario
Out of Obscurity
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Name: Cromix
Type: Rock/Dark
Base Stats: 105 / 70 / 120 / 40 / 97 / 78 | Total: 510
The idea for the base stats is that Diamond has had a long lifespan, hence the higher HP, and is not very physically sturdy, and can be broken relatively easily compared to some rocks, however the sheer size of these diamonds allow Cromix to do damage with them superior to Onix's rocks, as well as their "hardness" to keep up some good defenses. Its special defense relates to how diamonds are rather resilient to things that would much mroe easily wear rocks, etc. Its speed is raised due to the smoother, lighter diamonds compared to Steelix's heavy steel or Onix's jagged rocks.
Yeaaaaaah that summary sucked BUT I GOT IT DONE.
Edit: OMG Ninja theres two Cromixes
Edit2: Actually theres a lot of instances in which stats go DOWN in evolution. Like, a LOT.