Play them, attack, and replace them on the next draw
However, only ST10-002-monkeydluffy is a competitively viable option among the three Leaders
First introduced in Pokmon Red and Blue, Clefable holds the Pokdex number #36
It can still be slow and low-impact against decks that go way over the top, like Green Devotion, but if you just pay attention to how you feel when your opponent casts it against you on turn two in Limited, you might realize that the impact of that card is high enough that it demands serious exploration in Constructed
Kenrith can give them trample and haste for one red mana, and if Tatsunari has made them difficult to block I should be able to put the fear of Frog into at least one tablemate
I don't see any information on who is the seller and who is the buyer