101Leafy researched the games.
Sea Abyss

Plesioth-based Gunlance. Its shots hit like a massive tidal wave. Shelling Lv4
| Class | Gunlance |
|---|---|
| Rarity | 10 |
| Attack | 575 |
| Water | 400 |
| Slots | 1 |
| Price | 110,000z |
Upgrades
| Upgraded from | Sea God Leviathan |
|---|
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 758.