Pokmon who have sat on the board for at least one turn can be freely upgraded by placing an Evolution on them, which have larger health pools and stronger moves at the cost of usually being more Energy intensive
Scroll down for even more confirmation about this theory, we think this is almost certain Merlin Squirrel
It will see some constructed play but it won't be worth squat
Though Valiant Protector's ultimate ability (which provides a creature with +1/+1 counters equal to your life total and trample) could reliably close out a game, the fact that it requires a staggering eleven loyalty to activate makes the chances of it being used rather slim
In multiplayer formats like Commander, instant-speed interaction tends to be heavily favored over sorcery-speed alternatives when evaluating cards in that context I would adjust my assumptions to test how good a card is if it never makes it to my end step
The mechanic is also used so much that its not clear what is happening to cards like Nomad Decoy and Masked Gorgon when they power up