Overview:

This five-color Eldrazi deck helmed by Ulalek, Fused Atrocity focuses on explosive ramp into massive colorless threats while leveraging spell/ability duplication. The strategy revolves around deploying high-impact Eldrazi creatures that trigger annihilator and cast triggers, amplified by Ulalek's unique copy engine. Key support comes from cost reducers like Urza's Incubator and Eye of Ugin, while Echoes of Eternity and Kozilek's Unsealing create overwhelming value. The deck aims to win through annihilator-fueled combat, repeated cast triggers from copied spells, and synergies like Forsaken Monument's mana amplification.

Primer:

Core Strategy Execution:

1. Accelerated Setup (Turns 1-4): Prioritize Sol Ring, Mana Vault, and land-based ramp like Eldrazi Temple. Use Burgeoning/Exploration for land drops and Skyshroud Claim/Nature's Lore for color fixing. Deploy cost reducers like Urza's Incubator early.
2. Commander Deployment (Turns 3-5): Cast Ulalek once 5+ mana is available. Protect immediately with Lightning Greaves or Swiftfoot Boots. The commander enables critical mass turns when paired with Eldrazi casts.
3. Value Engine Activation (Turns 4-7): Chain Eldrazi spells to trigger Ulalek's copy effect and synergies:
   • Echoes of Eternity doubles every cast colorless spell
   • Kozilek's Unsealing generates tokens and card advantage
   • Sire of Stagnation punishes opponents' land drops
4. Closing the Game:
   • Annihilator Overload: Multiple attack phases with Kozilek, Butcher of Truth or Ulamog, the Ceaseless Hunger copied via Ulalek
   • Mana Combos: Darksteel Monolith enabling free casts paired with Forsaken Monument's mana doubling
   • Planeswalker Ultimates: Ugin, Eye of the Storms fetching multiple wincons

Mulligan Priorities:

• Keep hands with 2-3 lands including color sources (Command Tower, shocklands)
• Prioritize early ramp (artifact mana > land-based) and at least one cost reducer
• Ensure access to at least one protection piece (boots/greaves) or countermagic
• Avoid hands clogged with multiple 7+ CMC spells without acceleration

Key Tips:

• Time All Is Dust after establishing board presence with indestructible Eldrazi
• Use Emergence Zone/Alchemist's Refuge to flash in threats during opponents' turns
• Volrath's Stronghold recovers key Eldrazi for recast triggers
• Thespian's Stage copies utility lands like Eye of Ugin or Urza's Saga
• Gitaxian Probe helps time counterspells and assess safety for big turns

Weaknesses:

Critical

• Commander-dependent strategy: Repeated removal of Ulalek cripples copy engine
• Vulnerable to Drannith Magistrate/Cursed Totem shutting off key mechanics
• Struggles against fast combo decks due to limited interaction (only 3 counterspells)

Moderate

• Blood Moon/Back to Basics disrupts 5-color mana base
• Sacrifice effects bypass indestructible Eldrazi
• High life payment from painlands compounds with The One Ring/Mana Vault

Minor

• Limited graveyard recursion beyond Spawnbed Protector
• Deflecting Swat/Bolt Bend can redirect targeted removal

Most Important Cards:

• Ulalek, Fused Atrocity (Copy engine enabler)
• Echoes of Eternity (Spell/trigger duplication)
• Eye of Ugin (Tutor + cost reduction)
• Forsaken Monument (Mana amplification + lifegain)
• Darksteel Monolith (Free spell enabler)
• Urza's Incubator (Critical cost reduction)
• Kozilek, Butcher of Truth (Card draw + annihilator)
• The One Ring (Protection + card advantage)
• Ugin, Eye of the Storms (Removal + game-ending ult)
• Rhystic Study (Early game card flow)

Attribute Ratings:

Speed: 7/10

• Capable of T4 Ulalek into T5-6 annihilator swings or monument-powered combos, though reliant on drawing explosive ramp.

Resilience: 5/10

• Limited protection beyond equipment, though indestructible Eldrazi and Selective Obliteration provide some staying power.

Consistency: 7/10

• Strong ramp package and Ancient Stirrings/From Beyond tutors mitigate variance, but lacks redundancy for key noncreature pieces.

Interaction: 4/10

• Spot removal and two counterspells provide minimal disruption, relying more on board presence than active interaction.

Rating Justification:

This deck demonstrates optimized ramp and threat density for T5-7 wins through overwhelming Eldrazi synergies, but its commander dependency and limited interaction cap its ceiling. The combination of high speed (7) and moderate resilience (5) aligns with the "Focused Competitive" tier's T5-6 benchmark.

Power level: 7.0 - 7.5