basic onix pokemon card Pokemon 151 [SV2a 095/165] 'Onix U' SV2A-095-165-JP Colorless Retreat Cost Onix - 69/100 - Common

You might want to include it if youre playing a face-down deck, and turning it face up but getting 3 mana in exchange is a nice addition

It also has the useful attack Chaos Wheel, which for the cost of 1DCE, 1-grass, and 1-psychic, deals a damage of 100, while also locking the opponent from using any Stadium, Tool, or Special Energy card during their next turn.

But if you can potentially deal more than 20 damage in just two turns, with a "cashback" if the opponent does try to delete your pumped creature, then the dice usually becomes well worth rolling

Generally, managing this involves disrupting what the combo deck is trying to do, as their kill will be faster than yours if left unchecked