It isn't recommend against Calyex Ice-Rider but.... yes.
252+ SpA Life Orb Dark Aura Yveltal Dark Pulse vs. 248 HP / 8 SpD Calyrex-Ice: 398-468 (98.7 - 116.1%) -- 87.5% chance to OHKO
And in that 1v1 situation...... no one brings in such way. Yveltal comes in to revenge kill, dynamaxes, then wrecks havoc. Max Airstream from Life Orb deals like 87% to Xerneas. If they use Geomancy and not dynamax, then you win. Ask ProfDellDell, I used that on him.