アイアンクラッド

• Type: Attack
• Cost: 2
• Effect: Deal 12 damage. The next Attack you play costs 0.

Upgraded

• Cost: 2
• Effect: Deal 18 damage. The next Attack you play costs 0.

A Cost 2 attack dealing 12 damage (18 upgraded), which then makes the next attack cost 0 — a chain-type card. Its own damage is mediocre, but the follow-up free attack is powerful, effectively functioning as "2 cost to unlock a high-cost attack." Upgraded 18 damage also gives it solid stand-alone damage. Combined with Skull Bash (3 cost, 32 damage) or Whirlwind, it enables explosive burst turns. Shines especially in attack-heavy decks built around cost chaining.

Right after Ruthless, play the highest-cost attack (Skull Bash, Whirlwind, Trample) to maximize the free cost. Chaining Ruthless → Skull Bash → next Ruthless → Skull Bash produces 50+ damage on 2+0 cost. Hand sequencing is critical — use draw manipulation or Headbutt to line up the next attack after Ruthless. Paired with Juggling (power that copies every 3rd attack), you can reliably chain attacks and ride Ruthless's benefit.

• Skull Bash: Cost 3, 32-damage high-power attack. Ruthless makes it effectively 2-cost 30+ damage.
• Whirlwind: X-cost AoE. Free-attacking Whirlwind off Ruthless, or saving Energy for a later Whirlwind turn, is strong.
• Juggling: Power that copies every 3rd attack. Supports attack spam so Ruthless's free cost always lands on something useful.
• Wicked Blade: Skill that adds a random 0-cost attack to hand this turn. Combines with Ruthless's free cost to chain multiple attacks.
• Headbutt: Attack that places a discard on top of the draw pile. Queue the card you want to free-cast after Ruthless at the top of next turn.