Overview:

This Toxrill, the Corrosive deck combines board control with poison proliferation. The strategy leverages Toxrill's slime counters to weaken opponents' creatures while using infect/toxic threats and proliferate effects to deliver poison kills. It employs counterspells, removal, and card advantage to maintain control until either poison counters or commander damage secure victory.

Primer:

Core Strategy: The deck operates as a Dimir control shell with dual win conditions:

1. Poison Proliferation: Deploy infect creatures (Blighted Agent, Ichor Rats) and proliferate engines (Contagion Engine, Experimental Augury) to reach 10 poison counters.
2. Toxrill Dominance: Leverage the commander's board-wide debuff to create slug tokens for card draw, while threatening with a 7/7 body for potential commander damage.

Key Phases:

1. Early Game (Turns 1-4): Set up mana (Myr Convert, Glistening Sphere), disrupt opponents with counterspells (Daze, Mana Leak), and deploy early infect threats.
2. Mid Game (Turns 5-7): Cast Toxrill to start generating slime counters. Use proliferate triggers to accelerate poison while controlling the board with targeted removal (Sheoldred's Edict, Wash Away).
3. Late Game (Turns 8+): Close out with either poison counter proliferation, overwhelming slug token armies, or commander damage from an unchecked Toxrill.

Mulligan Priorities:

• Keep hands with 3 lands and early interaction/proliferate
• Prioritize T1-T2 plays like Bilious Skulldweller or Gitaxian Probe
• Avoid hands without blue/black sources or late-game-only cards

Key Tips:

• Time Toxrill casts post-wraths for maximum impact
• Use proliferate on end steps to maximize slime counter triggers
• Sacrifice slugs to Staff of Compleation for card draw
• Protect critical poison enablers like Ichor Rats with counters

Weaknesses:

Critical:

• Relies on fragile 1-toughness infect creatures for poison plan
• No infinite combos or deterministic win conditions
• Heavy commander dependency (3+ removals cripple strategy)

Moderate:

• Limited poison redundancy (only 5 direct infect sources)
• Slow poison clock without proliferate support

Minor:

• Graveyard recursion exists but isn't essential (Voidwing Hybrid, Mission Briefing)

Most Important Cards:

• Ichor Rats
• Contagion Engine
• Hullbreaker Horror
• Phyrexian Obliterator
• Staff of Compleation
• Diabolic Tutor
• Phyresis Outbreak
• Narset, Parter of Veils
• Notion Thief
• Blighted Agent

Attribute Ratings:

Speed: 5/10

• Earliest poison win: T6-7 with perfect proliferate draws
• Toxrill typically impacts board T5-6
• Lacks fast mana or cost reduction

Resilience: 6/10

• 12 counterspells protect key plays
• Multiple card advantage engines (Toxrill tokens, Phyrexian Arena)
• Weak to targeted land destruction (relies on Command Tower, Choked Estuary)

Consistency: 6/10

• 5 tutors (including Diabolic Tutor, Mission Briefing)
• 15+ card draw effects
• Multiple proliferate redundancies

Interaction: 8/10

• 16 targeted removal/counters (5 at instant speed)
• Board wipes scale with poison (Phyresis Outbreak)
• Hullbreaker Horror provides recurring bounce

Rating Justification:

This deck sits between Optimized Casual (5.0) and Focused (6.0). It has:

• Better interaction than typical 5.0 decks
• More redundancy than 5.5 lists
• Slower clock than 6.0 decks
• Less combo potential than 6.5+ strategies

Key differentiators from 6.0:

• No infinite mana/damage combos
• Relies on combat damage for secondary wincon
• Limited stax elements

Power level: 5.5 - 6.0