101Leafy researched the games.
Plesioth Azureblade

Not merely a Sword, this crystal weapon launches a jet of water upon contact.
| Class | Great Sword |
|---|---|
| Rarity | 6 |
| Attack | 816 |
| Water | 620 |
| Slots | 0 |
| Price | 55,000z |
Upgrades
| Upgraded from | Plesioth Crystasword |
|---|---|
| Upgrades into | Plesioth Wave Sword |
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 682.