Solidarity

Where a true Fog like Holy Day or Tangle simply zeroes out combat damage for the turn, this leaves your blockers and attackers swinging on offense while bracing them against everything pointed back. Four mana is steep for what amounts to a defensive trick, and that price buys a meaningfully different transaction: your creatures still deal their damage, still trade up in combat, still kill what they block. The +0/+5 is broad enough to swallow most damage-based removal and X-burn of its era, and instant speed lets you hold it as ambush insurance, daring an opponent to alpha-strike into a board you can suddenly make survive. The design tension lives in that asymmetry: a Fog protects the player who is behind, while this protects the player who is ahead and wants to keep attacking. It is a combat blowout dressed as a defensive trick, rewarding the player who commits to the board and punishing an opponent for joining them there. The rate has aged poorly against cheaper, more flexible toughness-pumps, but the structural idea (resilience without surrendering the attack step) is the through-line that keeps mass +0/+X effects in white's pie.