Holy Orb of Antioch
The Holy Orbs of Antioch were first created by Artificer Antioch. They are comprised of a standard grenade filled with high explosives and sacred ungents which are especially effective against the impure and wicked. Notably carried into battle by the Black Templars, they are also used by other Space Marines and forces of the Inquisition. They are all rigged with a five-second fuse and are individually crafted for excellent quality and reliability.
The Holy Orb of Antioch is possibly a reference to the Holy Hand Grenade of Antioch that appears in the comedy film Monty Python and the Holy Grail. The Grenade is deliberately patterned after the Sovereign's Orb, one of the British Crown Jewels. Also, the Grenade's user is instructed to count to three and then throw it, but King Arthur mistakenly says "five" when he means "three", as he does throughout the film.