101Leafy researched the games.
Black Dragon Sword

The Sword of Fatalis. "Born of the Dragon's life blood, vent thy fury North!"
| Class | Sword |
|---|---|
| Rarity | 8 |
| Attack | 294 |
| Dragon | 240 |
| Affinity | -20% |
| Slots | 0 |
| Price | 100,000z |
Upgrades
| Upgraded from | Black Sword |
|---|---|
| Upgrades into | True Blk Dragon Swd |
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 706.