If a spartan wielding an energy sword preforms an aerial assassination on another spartan both player characters will play the death animation. Below is a gif of the glitch in question I recorded earlier today on MCC PC Steam. I’m fairly certain this animation bug is in all versions of the game. It’s been a bug that was never fixed on the original version of Halo Reach on the Xbox 360.
I never knew that, ha. That is funny.