Activate Thraben Doomsayer by tapping it, creating a 1/1 Human token.
Human token enters the battlefield, triggering Intruder Alarm, untapping all creatures.
Repeat

Infinite creature tokens

Infinite ETB

Infinite mana creatures you control can produce

Infinite untap of creatures you control

Intruder Alarm

Thraben Doomsayer

Activate Thraben Doomsayer by tapping it, creating a 1/1 Human creature token.
Activate Ashnod's Altar by sacrificing the Human, adding {C}{C}.
When the Human dies, Thraben Doomsayer triggers, untapping Thraben Doomsayer.
Repeat.

Infinite LTB

Infinite sacrifice triggers

Infinite death triggers

Infinite colorless mana

Infinite damage

Thornbite Staff

Ashnod's Altar

Activate Thraben Doomsayer by tapping it, creating a 1/1 Human creature token.
When the Human enters the battlefield as a Pirate due to Maskwood Nexus, Coercive Recruiter triggers, untapping Thraben Doomsayer.
Repeat.

Coercive Recruiter

Maskwood Nexus

Activate Thraben Doomsayer by tapping it, creating a 1/1 Human creature token.
When the Human enters the battlefield as a Pirate due to Conspiracy, Coercive Recruiter triggers, untapping Thraben Doomsayer.
Repeat.

Conspiracy

Activate Thraben Doomsayer by tapping it, creating a 1/1 Human creature token.
When the Human enters the battlefield as a Pirate due to Xenograft, Coercive Recruiter triggers, untapping Thraben Doomsayer.
Repeat.

Xenograft

Activate Thraben Doomsayer by tapping it, creating a 1/1 Human creature token.
When the Human enters the battlefield as a Pirate due to Arcane Adaptation, Coercive Recruiter triggers, untapping Thraben Doomsayer.
Repeat.

Arcane Adaptation

Activate Necrotic Ooze using Thraben Doomsayer's ability by tapping it, creating a 1/1 Human creature token.
Activate Necrotic Ooze using Grimgrin's ability by sacrificing the Human, untapping Necrotic Ooze and putting a +1/+1 counter on it.
Repeat.

Combos with "Thraben Doomsayer"