101Leafy researched the games.
Blood Flute+

Red Hunting Horn made from wrapped Red Khezu hide. Its color is very unsettling.
| Class | Hunting Horn |
|---|---|
| Rarity | 9 |
| Attack | 1092 |
| Thunder | 400 |
| Slots | 1 |
| Price | 90,000z |
Upgrades
| Upgraded from | Blood Flute |
|---|---|
| Upgrades into | Brute Flute |
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 738.