101Leafy researched the games.
Indigo Ogre Sword

Supreme Dragonsword. Causes even mountain like wyverns to tremble with fear.
| Class | Sword |
|---|---|
| Rarity | 10 |
| Attack | 196 |
| Dragon | 520 |
| Slots | 2 |
| Price | 140,000z |
Upgrades
| Upgraded from | Azure Ogre Sword |
|---|
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 704.