WTF no. No open u's. Puff got it after e and r, DinoBrat got it after like 7 letters. CuCN revealed the last 3 letters.
f i _ b u l _ e t r (10)

Small hint

Big hint

Guessed Letters: a, o, e, r, s, i, b, u, t, n, l, d, f, q
Guessers: Propheon (5), Treldon, (5), Kirby (4)
The Word Was: Fimbulvetr. An A Rank Anima Tome in Fire Emblem