Silverquill Counters v1.9 (EDH / Commander)

Breena, the Demagogue leads a politically charged, active deck designed to influence and benefit from pitting opponents against each other. Go tall with +1 counters and make Breena a voltron threat. This build packs a lot of removal and protection to further influence opponent decisions if they choose to attack you instead of your opponents.

Strategies:

Low to the ground, evasive creatures and protection are favored to allow early and regular yet light attacks on opponents, triggering Breena's card draw and counters without presenting a major threat. Keep attacks small as +1 +1 counters accumulate before using overt force.

Ayara's Oathsworn - Menace. Low to ground. Adds +1 counter on player damage. Strat: time it so Breena can add two +2 counters to Ayara's on attack to activate tutor. Use Fain or Retribution to reset Ayara's.
Blade of the Oni - Menace. Low to ground. Consider attaching to Breena to further voltron strategies later.
Dauthi Voidwalker - Shadow (evasion). Low to ground. Graveyard hate.
Soltari Visionary - Shadow (evasion). Mobile removal.
Spirit en-Dal - Shadow (evasion). Forecast in upkeep to grant any creature shadow (great early to get triggers through, great late to get voltron Breena or other heavy hitter through).
Abu Ja'far - Early, more versatile form of deathtouch (evasion). Low to ground.
Orzhov Advokist - Free +1 counters for all, but they can't attack you if they take.
Academy Rector - Mobile tutor which people avoid killing so as not to give you a timely enchantment straight to the battlefield.
Mother of Runes - Low to ground. Mobile protection to get your attackers through and keep Breena safe.
Giver of Runes - Low to ground. Mobile protection to get your attackers through and keep Breena safe.
Mirran Crusader - Low to ground with built in protection to get attacks through. Double strike quickly potent with +1 counters.
Triumphant Adventurer - First strike + deathtouch upon attack (Evasion). Low to ground. Dungeon bonus.
Bastion Protector - Mobile anthem & defence for Breena.
Maddening Imp - Flying (evasion). Force all creatures an opponent controls to attack. Works great once you have Teysa or No Mercy in play.
Drumbellower - Mobile pseudo-vigilance for your creatures. Keep blockers up and opponent attacks elsewhere.
Shaile, Dean of Radiance // Embrose, Dean of Shadow - Flying (evasion). Low to ground. +1 counter generator.
Shadrix Silverquill - Flying (evasion). +1 counter generator. Death Knell.
Teysa, Envoy of Ghosts - Protection from creatures (evasion). Passive threat to would-be attackers.
Mikaeus, the Lunarch - Mobile +1 counters factory.
Nils, Discipline Enforcer - Mobile + 1 counter generation. +1 counters become tax to opponents.
Fain, the Broker - Mobile toolbox
Felisa, Fang of Silverquill - Flying (evasion). Board-wipe deterrence.
Athreos, Shroud-Veiled - Indestructible. Steal / protect creatures.
Preacher of the Schism
Righteous War (enchantment) - Protects your creatures from removal colors and helps provide your attackers with openings.
Duelist's Heritage (enchantment) - Your creatures are harder to block with double strike. Use on opponent creatures for political favor and to control the board.
Noble Heritage (enchantment) - Adds +1 counters and protection from opponents.
Forbidden Orchard (land) - Use the tokens politically to allow allies to attack.
Hive of the Eye Tyrant (land) - becomes a creature with evasion.

Walk softly but carry a big stick. This build offers a wide array of removal and deterrence to guide action and threats away from your board state.

Deathbringer Liege
Constable of the Realm
Hopeful Initiate
Author of Shadows
Unstable Glyphbridge // Sandswirl Wanderglyph
No Mercy
Season of the Witch
Anguished Unmaking
Vanishing Verse
Damn
Excavation Technique
Promise of Loyalty
Tragic Arrogance
Vindicate
Ondu Inversion // Ondu Skyruins

Honorable Mentions

Hero of Bretagard - Possible win-con as abilities mount through +1 counter generation and accumulation.
Reidane, God of the Worthy // Valkmira, Protector's Shield - Flying (evasion). Mobile tax.
Cruel Sadist