Tayam, Luminous Enigma | Mortician Beetle | Ashnod's Altar

(and one other card)

Activate
Ashnod's Altar by sacrificing
Geralf's Messenger, adding ({C} magic symbol) ({C} magic symbol) .
Geralf's Messenger's undying ability and
Mortician Beetle trigger.
Resolve the
Geralf's Messenger trigger, returning it from your graveyard to the battlefield with a +1/+1 and a vigilance counter.
Geralf's Messenger enters the battlefield, causing target opponent to lose 2 life.
Resolve the
Mortician Beetle trigger, putting a +1/+1 counter on it.
Activate
Tayam by paying ({3} magic symbol) , removing a +1/+1 counter from
Mortician Beetle and removing both counters from
Geralf's Messenger.
Holding priority, activate
Ashnod's Altar by sacrificing
Geralf's Messenger, adding ({C} magic symbol) ({C} magic symbol) .
Geralf's Messenger's undying ability and
Mortician Beetle trigger.
Resolve the
Geralf's Messenger trigger, returning it from your graveyard to the battlefield with a +1/+1 and a vigilance counter.
Geralf's Messenger enters the battlefield, causing target opponent to lose 2 life.
Resolve the
Mortician Beetle trigger, putting a +1/+1 counter on it.
Activate
Ashnod's Altar by sacrificing
Geralf's Messenger, adding ({C} magic symbol) ({C} magic symbol) .
Mortician Beetle triggers, putting a +1/+1 counter on itself.
Resolve the
Tayam ability from step 6, causing yourself to mill three cards and return
Geralf's Messenger from your graveyard to the battlefield.
Geralf's Messenger enters the battlefield, causing target opponent to lose 2 life.
Repeat.

Infinite +1/+1 counters on
Mortician Beetle.
Infinite colorless mana.
Infinite death triggers.
Infinite ETB.
Infinite lifeloss.
Infinite LTB.
Infinite sacrifice triggers.
Infinite self-mill.
Put all permanents with a mana value of three or less from your library and graveyard onto the battlefield.