Activate Bloodline Keeper's first ability by tapping it, creating a 2/2 Vampire creature token with flying.
Vampire token enters the battlefield, triggering Intruder Alarm, untapping all creatures.
Repeat

Infinite creature tokens

Infinite creature ETB

Bloodline Keeper // Lord of Lineage

Intruder Alarm

Activate Necrotic Ooze using Bloodline Keeper's first ability by tapping it, creating a 2/2 Vampire creature token.
Activate Necrotic Ooze using Grimgrin's ability by sacrificing the Vampire, untapping Necrotic Ooze and putting a +1/+1 counter on it.
Repeat.

Infinite +1/+1 counters on a creature

Infinite death triggers

Infinite creature LTB

Infinite creature sacrifice triggers

Grimgrin, Corpse-Born

Necrotic Ooze

Activate Bloodline Keeper by tapping it, creating a 2/2 Vampire creature token.
When the Vampire enters the battlefield as a Pirate due to Maskwood Nexus, Coercive Recruiter triggers, untapping Coercive Recruiter.
Repeat.

Coercive Recruiter

Maskwood Nexus

Activate Bloodline Keeper by tapping it, creating a 2/2 Vampire creature token.
When the Vampire enters the battlefield as a Pirate due to Conspiracy, Coercive Recruiter triggers, untapping Coercive Recruiter.
Repeat.

Conspiracy

Activate Bloodline Keeper by tapping it, creating a 2/2 Vampire creature token.
When the Vampire enters the battlefield as a Pirate due to Arcane Adaptation, Coercive Recruiter triggers, untapping Coercive Recruiter.
Repeat.

Arcane Adaptation

Activate Bloodline Keeper by tapping it, creating a 2/2 Vampire creature token.
When the Vampire enters the battlefield as a Pirate due to Xenograft, Coercive Recruiter triggers, untapping Coercive Recruiter.
Repeat.

Combos with "Bloodline Keeper // Lord of Lineage"