Jace's Defeat

In Commander, Jace's Defeat is a narrow counterspell — blue is everywhere, so the counter clause fires often, but two mana for a conditional counter that only hits blue is competing against Counterspell and Arcane Denial, both of which hit everything. The exile rider is genuinely useful against commanders like Teferi, Time Raveler or Narset, Parter of Veils that get recast from the command zone, but that upside doesn't clear the bar over unconditional options. In Legacy and Vintage, blue dominance makes the counter relevant more often, but those formats have access to Force of Will and Daze, so Jace's Defeat doesn't make cuts. Modern and Pioneer have enough blue threats that the condition is rarely a dead card, yet the same displacement problem applies — you're crowded out by better options at the same cost.