Corsairs of Umbar

Mana cost: {3}{U}
Type: Creature — Human Pirate
Power / toughness: 3 / 3
Set: Tales of Middle-earth Commander #421 (rare)
Price: $4.79 USD

{2}{U}: Target Goblin, Orc, or Pirate can't be blocked this turn.
Whenever this creature deals combat damage to a player, amass Orcs 3. (Put three +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.)

Corsairs of Umbar has 3 printings, first in Tales of Middle-earth Commander (2023). EDHREC ranks it #6,056 among Commander cards. It appears most in Sauron, the Dark Lord decks (16,555 on EDHREC). 1 public deck on TCG runs it. It has 8 official rulings.

Legality

commander: legal
legacy: legal
vintage: legal
pauper: not legal
modern: not legal
pioneer: not legal
standard: not legal
brawl: not legal

Public decks that run Corsairs of Umbar

Hosts of Mordor - Tales of Middle-earth Commander, led by Sauron, Lord of the Rings

Commanders that run Corsairs of Umbar most

Deck counts from EDHREC.

Often played with Corsairs of Umbar

Cards that show up in the same decks on EDHREC.

Rulings

2023-06-16: 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.
2023-06-16: 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.
2023-06-16: Activating Corsairs of Umbar's first ability after a Goblin, Orc, or Pirate has become blocked won't cause that creature to become unblocked.
2023-06-16: Amass abilities are now written as "amass [subtype] N." Previous cards with amass have received errata to say "amass Zombies N."
2023-06-16: 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.
2023-06-16: 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.
2023-06-16: 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.
2023-06-16: 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.