Etrata, the Silencer + Blade of Selves + Mirror Gallery + Parallel Lives + Doubling Season

Etrata, the Silencer

Blade of Selves

Mirror Gallery

Parallel Lives

Doubling Season

How it works

1. Declare Etrata as an attacker, attacking an opponent that owns at least two cards in exile with hit counters on them.
2. Etrata's myriad ability triggers, creating four copies of it attacking each other opponent.
3. Deal combat damage with each Etrata, triggering their abilities.
4. Resolve the first Etrata ability, causing the opponent dealt damage by it to exile a creature they control with a hit counter on it, and lose the game if they have at least three cards in exile with hit counters on them.
5. Repeat step 4 for each remaining trigger.