Bug: In the Mars Lighthouse, in the same room you defeat the Flame Dragons in, return after you have defeated the Flame Dragons and fire off the cannon. A crack will appear where the ice was, even though there is no ice.
Plot hole: Even if you've acquired Piers's ship before visiting Garoh (a city populated by werewolves), when you first set sail in Piers's ship, Sheba will say, "We've already met werewolves."