Mordor Muster

You draw a card and you lose 1 life.
Amass Orcs 1. (Put a +1/+1 counter 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.)

Sol Ring

Mauhúr, Uruk-hai Captain

Menace
If one or more +1/+1 counters would be put on an Army, Goblin, or Orc you control, that many plus one +1/+1 counters are put on it instead.

Merciless Executioner

When this creature enters, each player sacrifices a creature of their choice.

Uglúk of the White Hand

Whenever another creature you control dies, put a +1/+1 counter on Uglúk. If that creature was a Goblin or Orc, put two +1/+1 counters on Uglúk instead.

Orcish Siegemaster

Trample
Other Orcs and Goblins you control have trample.
Whenever this creature attacks, it gets +X/+0 until end of turn, where X is the greatest power among creatures you control.