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Amass Orcs X. Mill X cards. You may cast an instant or sorcery spell with mana value X or less from among them without paying its mana cost. (To amass Orcs X, put X +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)
Flashbackâ{3}{U}{R}, Exile X cards from your graveyard.
Amass Zombies works the same way, except you create a 0/0 black Zombie Army creature token if you don't control an Army. If the Army creature you chose isn't already a Zombie, it becomes a Zombie in addition to its other types. By combining cards with amass Orcs and amass Zombies, you can end up with an Orc Zombie Army.
Amass abilities are now written as "amass [subtype] N." Previous cards with amass have received errata to say "amass Zombies N."
If the spell has {X} in its mana cost, you must choose 0 as the value of X.
If you cast a spell "without paying its mana cost", you can't choose to cast it for any alternative costs. You can, however, pay additional costs, such as kicker costs. If the card has any mandatory additional costs, those must be paid to cast the spell.
If you don't control an Army, the Orc Army token you create enters the battlefield as a 0/0 creature before receiving counters. Any abilities that trigger when a creature with a certain power enters the battlefield, such as that of Mentor of the Meek, will see the token enter as a 0/0 creature before it gets +1/+1 counters.
If you want to cast one of the milled cards, you cast it as part of the resolution of Summons of Saruman. You can't wait to cast the spell later in the turn. Timing permissions based on the card's type are ignored.
In the rare case that you control multiple Army creatures (perhaps because you played a creature with changeling) while you amass Orcs, you choose which of your Army creatures to put the +1/+1 counters on. If that creature isn't an Orc, it becomes an Orc in addition to its other types.
Some cards refer to the "amassed Army." That means the Army creature you chose to receive counters, even if no counters were placed on it for some reason.
Some spells and abilities that amass Orcs may require targets. If each target chosen is an illegal target as that spell or ability tries to resolve, it won't resolve. You won't amass Orcs.
To amass Orcs N, if you don't control an Army creature, create a 0/0 black Orc Army creature token. Then you choose an Army creature you control and put N +1/+1 counters on it. If that Army isn't already an Orc, it becomes an Orc in addition to its other types.
