You can have up to 15 different lesson cards in your sideboard in BO3, but that wont allow you to have any other regular sideboard cards
Kona, Rescue Beastie Friendly, trusting, and keenly intelligent, Kona is unique amongst beasties in that she doesn't form attachments to individual survivors
Archon of Absolution Archon of Coronation Archon of Cruelty Archon of Emeria Archon of Falling Stars Archon of Justice Archon of Redemption Archon of Sun's Grace Archon of Valor's Reach Archon of the Triumvirate Archon of the Wild Rose Ashen Rider Blazing Archon Celestial Archon Ezrim, Agency Chief Guardian Archon Harmonious Archon Krond the Dawn-Clad Ornitharch Silent Sentinel Vengeful Archon
Given how much utility Commander decks often have in order to react to massive creatures and game-ending combos, a card with a high mana cost and additional setups like Jumbo Cactuar isn't the deadliest threat out there
Walking Ballista is the easiest payoff creature to disrupt, as the loop cannot proceed without first resolving Heliods activated ability or some similar lifelink-granting effect
If you dont need to stop a Swords to Plowshares thats targeting your commander, maybe that Negate can snag a Bolass Citadel or Teferis Protection instead
