This version of the Pokemon card doesnt have the best actual utility other than being quickly replaced by Boltund for its energy acceleration attack, but looking at it in the art, it doesnt seem to mind its role very much
This sudden price shift was likely the result of market manipulation, in which a group of individuals buys every copy of a card, then sells it at a higher, set price
Making tokens has always been something zombies have done anyway, and suddenly nerfing them with decayed feels odd
Combinations with cards like Shuko and Sylvan Safekeeper that target your creatures for no mana drew huge sums of cards and pumped mana into play
This made it easy to get back important cards such as Raigeki, Monster Reborn, or Change of Heart in the old-school days of Yu-Gi-Oh
Also, when 1 of your Pokmon becomes a Mega Evolution Pokmon, your turn ends