japanese pokemon 151 cards (3 Packs) Card Game SV2a Booster Pack (7 Per Pack) : Toys & Games Pokemon 151 Singles Pokemon 151 Booster Box (Japanese)

But how do you get it and what does it even do

You can only evolve one Pokmon per turn (and it cant be in the same turn in which youve introduced it into play)

Blighted Woodland Tap to add 1 colorless Tap, pay 3 generic, pay 1 green and sacrifice it to search your library for 2 basic land cards and put them on the battlefield tapped Escape Tunnel Tap and sacrifice it to search your library for a basic land and put it on the battlefield tapped Tap and sacrifice it to make target creature with power 2 or less unblockable this turn Evolving Wilds Tap and sacrifice it to search your library for a basic land and put it on the battlefield tapped Fabled Passage Tap and sacrifice it to search your library for a basic land and put it on the battlefield tapped

Yes, Mega Evolution cards are valuable due to collector demand, nostalgia from the XY era, and limited availability, with certain iconic Pokmon and Secret Rare versions commanding significantly higher prices