In practice, shuffling once is sufficient, but effects that care about you shuffling your library (like Psychogenic Probe, for example) will see that you've shuffled twice
Lands are often overlooked in many strategies, but as the lifeblood of the game, it can be a tremendous help to bring lands back from the graveyard
You can also get a fast start by putting Vengevines in your graveyard and powering them out on turn two
Its Block ability prevents your opponents Active Pokmon from retreating while Snorlax is in the Active Spot, making it a nightmare for decks that lack sufficient switching options
(?): Abyss Eye featuring Darkrai
If the copied creature was copying something else, then the token enters the battlefield as whatever that creature copied, with the stated exceptions