101Leafy researched the games.
Ultimus Apocalypse

A most evil weapon. It has passed through many hands via a chain of dark deaths.
| Class | Dual Blades |
|---|---|
| Rarity | 10 |
| Attack | 364 |
| Slots | 0 |
| Price | 150,000z |
Upgrades
| Upgraded from | Ultimus Celestials |
|---|
Upgrade tree from モンスターハンターポータブル 2nd G 公式ガイドブック (Enterbrain, 2008), page 716.