Kept secret by the Jakobs family, the Graveward's vault lay undisturbed for centuries beneath Jakobs Estate. Given holy charge to find the Eden-6 vault, the Children of the Vault assault the planet, while the Calypso Twins arrange a lethally hostile takeover of Jakobs corporation, acquiring by proxy not only the family's company, but its estate and, they hope, its secrets.
With vault and key located, the Calypsos—knowing vaults to be prisons, but not what this vault imprisons—lure the Vault Hunters into life-or-death combat with its prisoner, as Tyreen Calypso waits to feast on its power in death. Defeat follows defeat, however, as the dying Graveward's power is stolen from Tyreen by Patricia Tannis.
Where it glows yellow, the Graveward is vulnerable. Well-defined circular areas of its chest and head provide small, dependable targets, with damage multipliers of 1.4 and 1.2, respectively. Targets of opportunity include the large, glowing orbs in its hands (2.5 multiplier), readily attacked when a hand's armor is shattered by striking the arena floor.
The Graveward begins its fight by tilting the entire arena and sending a spread of corrosive spheres rolling downslope. Meanwhile, players slide toward fatal falls from the arena's edge. Halt sliding by either jumping continuously, or sheltering in pits in the arena floor. This attack will recur occasionally between the Graveward's more regular attacks. Due to the fact that the tilting attack causes the player to slide, a Snowdrift Artifact will worsen the effect.
The regular attacks target halves of the arena: left or right, front or back. Where it attacks next, the floor glows, aiding dodges. Initially, there are four such attacks:
- A straight punch with the right arm, dealing radiation damage to the left half of the arena.
- A right hook along the back, dealing radiation damage.
- Can rarely be replaced by a left swing that covers the same area.
- A left-handed hammer strike, dealing radiation damage to the right half of the arena.
- A corrosive breath attack to the front half while supporting itself on the edge.
After transitioning to phase two of the fight, the Graveward gains two additional attacks. Both are incendiary beam attacks. One shoots several beams from the glowing spots on top of its head, covering a line in the center of the arena, front to back. The other one is a beam from the object in its chest, sweeping across the entire arena. This beam can be avoided by staying at the very back of the arena and jumping over it.
When the Graveward uses its corrosive breath on the front half of the arena, it also summons Grogs, some of which can be corrosive badasses. Similarly, the straight right punch (hitting the left side of the arena) will spawn a few Jabbers. While not the most powerful, these creatures will build up if ignored and should be taken care of.
After damaging the Graveward below 2/3 and 1/3 of its health respectively, it will start a new phase, changing up its move set and order a little. Each of these are marked by it rearing up and falling onto the edge of the arena, remaining there for a couple seconds. In this state the Head crit spots are easy to hit - even with shotguns - and characters can wail on it. Afterwards, it will tip the arena, followed by an eye beam attack and a chest beam sweep before it returns to its regular move set. During this, it can still be damaged. If it is knocked down another 1/3 of its health while in this mode switch, it will not fall down and start it over, but instantly pick up in the next phase.