Umbris, Fear Manifest, Opposition Agent, Hive Mind, Mana Severance, and Blade of Selves

Prerequisites

• Umbris, Fear Manifest on the battlefield
• Opposition Agent on the battlefield
• Hive Mind on the battlefield
• Mana Severance in hand
• Blade of Selves on the battlefield
• Blade of Selves attached to Umbris
• Umbris does not have summoning sickness
• available

Steps

1. Cast Mana Severance by paying
2. Hive Mind triggers, causing each opponent to copy Mana Severance
3. Resolve each opponent's Mana Severance, searching for and exiling all land cards from their libraries
4. Resolve your Mana Severance, choosing not to exile any land cards from your library
5. Move to your combat step
6. Attack with Umbris
7. Umbris triggers, creating a token copy of Umbris for each opponent you have, with each token tapped and attacking a different opponent
8. Put all but one Umbris into your graveyard due to the legend rule
9. Umbris triggers for each Umbris token that enters and each Umbris token triggers for itself and each other Umbris that enters
10. Resolve the Umbris triggers, revealing no lands from opponent libraries and exiling each opponent library

Results

• Exile each opponent's library
• Near-infinitely large Umbris