Progenitor Mimic | Notorious Throng | Eternal Witness

Cards

Notorious Throng in hand.
Progenitor Mimic and
Eternal Witness on the battlefield.
Progenitor Mimic on the battlefield as a copy of
Eternal Witness.
You control at least one Rogue that does not have summoning sickness and cannot be blocked by an opponent.
({5} magic symbol) ({U} magic symbol) each turn available.

Deal combat damage to an opponent using a Rogue.
Cast
Notorious Throng for its prowl cost by paying ({5} magic symbol) ({U} magic symbol) , causing you to take an extra turn after this one.
At the beginning of your next upkeep,
Progenitor Mimic triggers, creating a token copy of
Eternal Witness.
When the
Eternal Witness token enters the battlefield, it triggers, returning
Notorious Throng from your graveyard to your hand.
Repeat.