The player skips each instance of the chosen step or phase this turn. This is a good way to make sure that people can either attack or cast spells in most cases, and it doesnt even impact you at all
That double-faced card text is a sign that it was a common in a set full of battles and dual-sided cards that represented compleated citizens of the multiverse
It also represents the first time that the region of Sinnoh became a permanent addition to the TCGs normal card pool, after the EX series concluded
You see many lists playing 1, not multiples
Its been nine years since Gatecrash released, but it had a good run of four to five years when it was the go-to choice of one-drop for Modern aggressive decks
You can pull off those counters for three cards, and if you managed to give it another counter, then you can keep it around (although I think it's better when you kill it)