pokemon japanese booster pack TCG: SV3a Raging Surf (Japanese) Japanese version Pokemon MEGA Evolution Inferno X

[4] Players attempt to use their Pokmon to deal damage and deplete the health of opposing Pokmon

The cards I cover can be impactful in any of Standard, Pioneer, Historic, Modern or Legacy

While skipping one-drops is doable, especially in slower decks, not being able to play three-drops as well means that playing Gyruda, Doom of Depths as your companion essentially means that you're guaranteeing you'll cast a maximum of four mana worth of spells (two two-drops) across the first three turns of the game, which is certainly too slow for older formats like Modern and Pioneer, and likely too slow for Standard as well

But that's with perfect card draws and average coin flips

YouTube (February 15, 2022)

If you cast a spell for which mana may be spent as though it were mana of any color, you may cast it for Leyline of Mutation's second ability's alternative cost and still spend mana as though it were mana of any color