101Leafy researched the games.
Hidden Gunlance

Gunlance of the darkest night. The black blades hide the gun well. Shelling Lv3
| Class | Gunlance |
|---|---|
| Rarity | 7 |
| Attack | 437 |
| Affinity | 40% |
| Slots | 1 |
| Price | 80,000z |
Upgrades
| Upgraded from | Rex Blast |
|---|---|
| Upgrades into | WanningMoonDarklance |
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 760.
Materials
NargaCuttingWing ×4, Nargacuga Tail ×3, Narga Brain Stem ×1, Hrd Monster Bone ×5