Overview:

This 5-color Sliver deck leverages The First Sliver's cascade ability to flood the board with synergistic creatures, rapidly scaling into overwhelming combat threats or combo finishes. The commander accelerates the strategy by chaining free spells, while backup commanders like Sliver Overlord and Sliver Queen provide redundancy and combo potential. Key win conditions include massive combat damage (amplified by Sliver Legion, Bonescythe Sliver, and infect via Triumph of the Hordes), infinite mana/token combos with Sliver Queen + Mana Echoes or Intruder Alarm, and alternative wins like Coalition Victory. The deck balances tribal synergy with high-powered staples like Mana Drain and Force of Will for protection.

Primer:

Core Strategy Execution:

1. Early Setup (Turns 1-3):
   Deploy mana fixers (Birds of Paradise, Ignoble Hierarch, fetchlands) and key Slivers like Manaweft Sliver/Gemhide Sliver for ramp. Training Grounds reduces Sliver Overlord/Sliver Queen activation costs.
2. Cascade Engine (Turns 4-5):
   Cast The First Sliver to trigger cascades, prioritizing low-CMC Slivers to maximize free spells. Use Realmwalker/Herald's Horn to maintain gas.
3. Win Condition Deployment:
   • Combat: Buff the board with Sliver Legion, Bonescythe Sliver, and Cloudshredder Sliver, then swing with Triumph of the Hordes or Kindred Dominance to clear blockers.
   • Combo: Tutor for Sliver Queen + Mana Echoes (infinite mana/tokens) or Intruder Alarm + mana Slivers (infinite untaps). Use Syphon Sliver for infinite life or Virulent Sliver for instant poison kills.

Mulligan Priorities:

• Keep hands with 2-3 lands, including a rainbow source (Command Tower, Cavern of Souls).
• Prioritize early ramp (dorks, Nature's Lore) and at least one key Sliver (mana generator or protection like Crystalline Sliver).
• Avoid hands lacking colored mana sources or with only high-CMC spells.

Key Tips:

• Use Homing Sliver's slivercycling to find answers/reactively.
• Cryptolith Rite turns your board into a mana engine for explosive turns.
• Protect key pieces with Fierce Guardianship and Force of Will – counter board wipes targeting your indestructible Sliver Hivelord.

Weaknesses:

Critical

• Board wipes bypassing indestructible (Toxic Deluge, Cyclonic Rift) can reset your momentum.
• Cursed Totem/Linvala, Keeper of Silence nullifies mana Slivers and combo activations.

Moderate

• Graveyard hate disrupts Patriarch's Bidding and Dregscape Sliver recursion.
• Rule of Law effects limit cascade chains and combo potential.

Minor

• Color-specific hosers (Engineered Plague naming Slivers) require Unnatural Selection to bypass.

Most Important Cards:

• Sliver Overlord (Tutor any Sliver, steal opponents' Slivers)
• Sliver Queen (Infinite token/mana combo enabler)
• Mana Echoes (Primary combo piece with Sliver tokens)
• Intruder Alarm (Untap engine for infinite mana/ETBs)
• The First Sliver (Cascade value engine)
• Cavern of Souls (Ensures uncounterable Slivers)
• Aura Shards (Artifact/enchantment control via ETBs)
• Rhystic Study (Card advantage in creature-heavy meta)
• Demonic Tutor (Finds any combo piece)
• Training Grounds (Reduces Overlord/Queen activation costs)

Attribute Ratings:

Speed: 7/10
Can threaten combo wins or lethal combat by T5-6 through cascades and tutors, though lacks T1-3 "oops I win" lines.

Resilience: 6/10
Multiple protection Slivers (Crystalline, Diffusion Sliver) and free counterspells help, but reliant on board presence for value.

Consistency: 8/10
12 tutors (including cascade chains), 10+ card draw engines, and tribal synergy ensure key pieces are accessible.

Interaction: 7/10
Runs premium removal (Assassin's Trophy, Cyclonic Rift) and counterspells, but light on artifact/enchantment removal beyond Aura Shards.

Rating Justification:

This deck operates at a high-power casual level with T5-7 win potential through both combat and combos, supported by robust tutoring and protection. While faster than precons, it lacks the speed (T3-4) and compact combos of true cEDH decks.

Power level: 6.5 - 7.0