Mistmoon Griffin from your graveyard to the battlefield.
Resolve the
Mistmoon Griffin trigger, failing to exile it as it is not in your graveyard and then returning Saffi from your graveyard to the battlefield.
Resolve the
Evereth ability.
Repeat.
Notes
If you have a way to kill
Evereth and ({1} magic symbol) ({BR} magic symbol) available, you can do so after putting a significant amount of +1/+1 counters on it to deal damage to each opponent using its second ability.
Results
Infinite +1/+1 counters on a creature.
Infinite creature ETB.
Infinite creature LTB.
Infinite creature sacrifice triggers.
Infinite death triggers.
Infinite damage.
Metadata
In 0 decks according to EDHREC.
Bracket Tag
This combo has been estimated to be Spicy (Bracket 3-4+).