crystal venom skarner was the healthiest iteration of him
all you really needed to do after that was make his Q something more interesting than an instant PBAoE but he fit the bill of a healthy bruiser otherwise with some of his power gated behind a condition of needing to stack up first and having an avoidable skillshot that gives him a way to close distance if he lands it
i don't even know if he needs a total overhaul, his kit is WAS really functional and if anything he's only been fucked by riot's reworks + Zac rework doing what Skarner's supposed to do but to potentially 5 people at once