101Leafy researched the games.
Fatalis Sickle

A most fatal giant scythe. Unhealable wounds torture the unlucky for centuries.
| Class | Long Sword |
|---|---|
| Rarity | 8 |
| Attack | 1008 |
| Dragon | 200 |
| Slots | 0 |
| Price | 100,000z |
Upgrades
| Upgraded from | Black Scythe |
|---|---|
| Upgrades into | LgndaryFatalisSickle |
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 696.