On its early turns, it doesn't seem to achieve much - play a land, fetch a land, create a puny plant token
The most dramatic crash this week is Greninja ex 214/167, crashing by nearly half when compared the the start of this year
With them we can draw more cards per turn (by default, it is one at the beginning of each turn), switch between active and benched Pokemon, heal our creatures' HP, and so on
Making our opponent discard in the midgame could easily prove disastrous, putting two nasty threats in easy reach of reanimation spells, for example
However, the payoff is huge
Its good against the supporting decks in the meta, but bad against the big menace of the format