Bolas's Citadel + Cauldron Familiar + Mortuary + Phantom Train

Mana needed: {B} if Cauldron Familiar is in your hand

B identity

Commander legal

The 4 combo pieces

How to execute it

  1. Cast Cauldron Familiar either from your hand or from the top of your library by paying {B} or 1 life respectively.
  2. When Cauldron Familiar enters, it triggers, causing each opponent to lose 1 life and you to gain 1 life.
  3. Activate Phantom Train by sacrificing Cauldron Familiar.
  4. When Cauldron Familiar dies, Mortuary triggers, putting Cauldron Familiar from your graveyard onto the top of your library.
  5. Resolve the Phantom Train ability.
  6. Repeat.

What the combo produces