From Halopedia, the Halo wiki
Retrieved from "https://www.halopedia.org/index.php?title=Hail_Mary&oldid=1172536"
In Halo 4 Plasma grenade sticks can award a Hail Mary medal from the grave, provided the player who threw the grenade respawns at a spawn point far enough from the target. In Halo 5: Guardians this is no longer the case. Players will however be awarded the medal in situations where they injure an opponent with a long-range grenade and said opponent is then finished off by fall damage, friendly fire, or Warzone AI.