101Leafy researched the games.
Great Bone Gunlance

Introductory Gunlance to polish one's skills. Strong, easy to use. Shelling Lv2
| Class | Gunlance |
|---|---|
| Rarity | 2 |
| Attack | 230 |
| Slots | 0 |
| Price | 1,400z |
Upgrades
| Upgraded from | Longhorn+ |
|---|---|
| Upgrades into | Wyvern Bone Gunlance, Average Hitter |
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 756.