Ignore this warning. In Minecraft 1.21.0, most texture packs are backward compatible. Click "OK" or "Use Anyway." 99% of textures will work. If you see missing textures on the Mace or Breeze, you need a patch (search "FlameFrags 1.21 Patch").
He clicked download.
He took a step toward the throne room's fireplace. The 180,000 embers swirled into a vortex. In the distance, he heard the voices of every lost player from 2014—building, laughing, dying. flamefrags 180k texture pack mcpe 1.21.0 download