101Leafy researched the games.
Midnight Blades

Jet-black Sword. Rumors say the sword's strange vibe is hiding the lives it's taken.
| Class | Sword |
|---|---|
| Rarity | 10 |
| Attack | 336 |
| Affinity | 40% |
| Slots | 2 |
| Price | 120,000z |
Upgrades
| Upgraded from | Hidden Edge |
|---|
Can also be made new at the smithy.
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.
Materials
ThickNargaScale ×6, HvyNargaTailSpik ×10, StrNargaCttngWng ×4, HvnlyNargaScale ×1