From FFXIclopedia, the free Final Fantasy XI encyclopedia

Job: Black Mage Family: Skeletons Crystal: Earth Weak to: Fire, Light Notorious Monster

Silverhook

Zone	Level	Drops	Steal	Spawns	Notes
Ship bound for Mhaura	68-70	Seawolf Cudgel (34%) Bone Chip (13.5%)	Bone Chip	1	A, H, HP
A = Aggressive; L = Links; S = Detects by Sight; H = Detects by Sound; HP = Detects Low HP; M = Detects Magic; Sc = Follows by Scent; T(S) = True-sight; T(H) = True-hearing; JA = Detects job abilities; WS = Detects weaponskills; Z(D) = Asleep in Daytime; Z(N) = Asleep at Nighttime

Notes:

• Spawns with the pirates on the ferry route from Selbina to Mhaura
• Much larger than other skeletons
  • Only spawns during the Pirate event on the ferry when the middle pirate on the pirate ship is wearing a Vermillion Cloak.
  • The middle Vermillion Cloak pirate does not gurantee that it will with the initial group of skeletons.
• Can spawn on any boat ride with pirate event including during the day time.
• Killable by: 4+ level 70+ characters, soloable by certain job/subjob combinations at 75. (see testimonials)
• Special Attacks: Sleep, Sleepga II, all Ancient Magic (Flood, Freeze, etc.), Blizzard III, Blizzaga II, Waterga III, Stun, Ice Spikes.

Video