The Hezen's/Hellmouth's Headcracker. (I see a helmet made of a patchwork of Minotaur armour/Hive Knight helmets, with a shard of a bladed Vex finger/a Knight swords jammed in it like it like it got stuck, and is now a makeshift crooked horn.)

An Exo, Ronin-13, rushed to her fireteam member on the tower, a peculiar helmet under his arm.
"I've been looking for you everywh-- what is that, Horus?"
Horus simply looked at her, raising one browplate.
"A Festival mask? It looks like you could drop a Skiff on that thing," she put her hands on her hips, "and it looks like you tried."
The Exo jerked a thumb towards Shaxx.
"What do you mean 'he asked me to put on a bigger show'?"
The Exo simply shrugged, not saying a word. Which garnered a confused, then shocked reaction in his old friend. His Ghost ducked from behind him, looking at her apologetically.
"He says--"
"I know what he says. I'm just confused what he means about Ra-8. Everybody remembers Ra, he's the one who dunked the tiebreaker Spark using his Novabomb during the Redjack finals. But that's just it, he was a Voidwalker, and moreover a Warlock, not a Strike--"
Revelations are like bricks. They're surprising when they hit you in the head. By the time Ronin had pulled her attention from the scorched poster behind Shaxx, Horus-9 had already slipped away, his Mark fluttering like a tattered robe behind him.

Exotic Titan Helmet

Perk: Wormfed synapses. Sprinting charged melees of any subclass path performs a headbutt animation. If you have the 'shoulder charge' melees equipped, you gain that distance. If not, you stop short and perform a different headbutt animation. Triggers health regen and restores melee energy. (Basically a cooler Skullfort, because I only, only know how to punch things in the face)