Puzzles
In the Labyrinth section of the dungeon, there are two secret doors that can be opened simply by killing all the Orcs in that area. They can be a little hard to find (it is a labyrinth after all), but kill them all and two secret doors will open revealing a chest for everyone to loot.
The two puzzles previously mentioned involve finding three objects for each within the Tower and placing them on altars in the exit room. One altar requires three crystals while the other requires three plants. They can be a little tricky to spot, but as long as your group of fearless adventurers works together and keeps their eyes open, you'll have no problems. Since killing Vansi doesn't result in a loot chest (unless you're playing during a special event), then solving these puzzles is the only way to make any chests spawn before you leave.
The three crystals (red, green, and blue) are the easiest to find. The red crystal is on a table in the room where you killed Mazred the Foul. The green crystal is in that general area. It's on a table within the Apprentice Chambers. The blue crystal is a little harder to locate, but at is at the edge of the pool at the bottom of the blue crystal garden. Walk around the edges of the pool of water and you'll see one crystal out of all the other blue crystals that has floating dust around it. When you get to the exit room, place all three crystals on the altar and a chest will appear.
The three plants are a little easier. The Starflower is on a table, once again in the room where you killed Mazred the Foul. The glow berries can be found at the fork in the Botanical Gardens, where going right and down leads not only to the Throg the Ravenous, but the final plant as well. Grab the Gingershroom he drops and you're all set. Place all three items on the other altar in the exit room and a chest will appear.
Ta-Dah!