A difficult thing to explain to new players is the tempo of a Commander game
As a bonus, Acid Rain's art shows it destroying not a tree but a statue, making it a flavor fail as well
When this creature becomes monstrous, tap up to four target creatures
More Than Meets the Eye (You may cast this card converted for .) Double strike, haste At the beginning of each opponent's upkeep, you may have that player gain control of Slicer until end of turn
the effects in bold above is important for 2 reason: 1) its important that the infamous "kaiju summon" distinctly says "tributing 1 monster you control" since normaly you supposed to unable to do that 2) sure these "Unknown Kaiju" is a sub-archetype of pre-existing Kaiju but since it share the same "Kaiju" naming convention you dont need to mention "Unknown Kaiju"
Combining this card with ways to double your tokens or ways to utilize sacrificing them before the end step, makes it a strong option to be playing