Evernight Shade dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
Resolve the
Bartolomé del Presidio ability.
Activate
Bartolomé del Presidio by sacrificing
Evernight Shade.
When
Evernight Shade dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
Evernight Shade enters and dies as a state-based action due to having 0 toughness. Its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
Resolve the
Bartolomé del Presidio ability from step 4.
Repeat from step 4.
Notes
If
Evernight Shade starts with a +1/+1 counter on it, then you may start the combo from step 4 instead.
Results
Infinite +1/+1 counters on a creature.
Infinite creature ETB.
Infinite creature LTB.
Infinite death triggers.
Infinite creature sacrifice triggers.
Metadata
Bracket tag
OddballBracket 2-3+
Probably 2 or 3, but hard to classify
1
2
3
4
5
1 · Exhibition5 · cEDH
Bracket tags are estimated from the cards and results of each combo, as a guideline rather than a strict classification.