dragon ball super supreme rivalry booster box - - Unison Warriors Set 04 (B13) Son Goku Dragon Ball Super Masters: Supreme

Once per turn: You can remove any number of Spell Counters from your field

As raytyger points out in the comments, this is very similar to the Mutate mechanic from Ikoria

Although the slightly larger quantity of the Serial Number Shanks card has thus far kept its value from rising to the heights of its Luffy counterpart, one must bear in mind that this card only hit the open market a few months ago and its value is still on the upswing

If you have a full party, you may cast a spell with mana value 4 or less from your hand without paying its mana cost

The down side is that you take 1000 points of burn damage during each of your standby phases as long as it is face-up on your field

If Gandalf the Grey leaves the battlefield (possibly because of the fourth mode of its ability) and then returns to the battlefield later, it will be a new object with no memory of the modes chosen when it was last on the battlefield