La cartea avem ca text:

Whenever Sidisi, Brood Tyrant enters the battlefield or attacks, put the top three cards of your library into your graveyard.

Whenever one or more creature cards are put into your graveyard from your library, put a 2/2 black Zombie creature token onto the battlefield.

Acum la partea de trigger cand ai pus in graveyard 5 carti din care aveai 2 creaturi, veni primi 2 zombie sau doar unul?

Acum conform http://youtu.be/UrN36mK5D1A?t=6m7s zice ca ai primi doar un zombie la trigger, dar nu mi se pare normal :)

Ca si conditie ai "Whenever one or more creature cards are put into your graveyard from your library". Poate fi 1 creatura, pot fi 5 creaturi. Trebuie sa fie > 0.
Ca efect, "put a 2/2 black Zombie creature token onto the battlefield".

There's no way around this. La un singur mill, primesti fie un zombie, fie nimic. Daca era cu mai multi zombie, de obicei e pus "for each" in text.

Da, un singur zombie indiferent cate creaturi pui in grave per mill. E worded 'one or more' in loc de 'for each' sau 'whenever a creature'.