Ok.This is more of a hint than a cheat,but it can still be very useful.After you beat Jack of Blades,toss the Sword of Aeons into the vortex.Then,go into Maze's room in the guild.In one of the book cases there should be a book called the History of the Guild,take it.A green dot should appear on your map.Go to the dot.It should have led you to the empty grave outside.Read the grave,and then Avo should start talking to you.You should recieve the sword Avo's Tear.