Thunderroc's Halo is a Nightmare Unique relic, hunted from Thunderroc in the Mortal Arena, always at item level 120. It is one of four Exceptional drops on its list — 2.5% of the Uniques that boss gives up, about 1 in 40 — and every kill rolls the list 5 times. It is built on Eternal Voidhalo Relic — step 6 of the Voidhalo Relic line, item level 80 and up.

It always rolls the same numbers: +12% Ultimate Generation, +20 Power, +18% Storm Damage, +25% Ultimate Generation, +48% Storm Damage, +64% Ultimate Generation, +45% Shock Effect and +570 Maximum Health.

One Unique drop in 40 is a Mythical copy: the same item carrying 15–25% Mythical Energy that boosts every stat on it and can never be changed; the 15% floor is 10 times as common as the perfect 25%.

On top of that it carries Thunderroc's Halo — Your Ultimate is attuned to Storm and calls 4 more strikes from the sky, each Shocking what it lands on; a full Shock Overloads, but your Armor is 15% lower.

It fires Arcing Spark on its own: Hits have a 20% chance to arc to a nearby enemy for 55% of the damage.

It leans into Storm and Shock.

Wearing it hands you Starfall.

“All of it. At once. Here.”