Quests

Quests can be obtained by speaking to Detox behind the counter in the Arcade after defeating COEN on the 3rd Floor. After completing a quest, you must return to Detox/Superscope 703 to turn it in, and the reward will be sent to the Rewards Box in your Waiting Room.

The first 10 Quests become available after defeating COEN on the 3rd Floor, another 10 become available upon reaching the 5th Floor, and more are unlocked as the player continues to reach new floors.

Generally speaking, Difficulty 1 Quests are gained on Floors 1-10, Difficulty 2 Quests on Floors 11-20, Difficult 3 Quests on Floors 21-30, and Difficulty 4 Quests on Floors 31-40.

Defeat All Enemies Quests
In quests that state you must climb from one floor to another, defeating all enemies while meeting a certain condition, you are required to kill every enemy on and between the floors listed. Any kills that occur due to Haters/Hunters, friendly fire, or environmental hazards will not count against you. You can use as many weapons as you need during any quest requiring a specific weapon or element, as long as the weapons fall into the specified category. When doing these quests, remember that you must also clear out any trap rooms, ambushes, and monster closets in order to complete the floor. The Treasure Hunter decal is helpful for these quests, as enemies will appear on the map with this decal equipped. The decal does not show enemies in wait for ambushes and trap rooms, however.

Tips
For examples of floors which contain a single tuber near an escalator:
 * Climbing Quests: You can do multiple climbing quests at the same time. It is also recommend that you pick up any Mushroom and Beast quests for the areas you're doing climbing quests in, as you'll probably see a lot of them on your way up the tower. Enemies hidden in vending machines do not count, so feel free to ignore those if you wish. If you're uncertain that you've defeated everything on a specific floor, wait for a few minutes by the escalator leading to the next floor, until you hear the Jackal alarm sound off; the alarm only occurs if all enemies on a floor are dead.
 * Treasure Tubers Quests: Treasure Tubers themselves are very rare to encounter, especially the Mk-2 and Mk-3 Tubers. When looking for them, it's best to find a floor with a single Tuber in it and simply use the escalators to go up and down between floors until a Treasure Tuber takes the place of the regular tuber. However, it can take a very long time before the Treasure Tuber spawns, so make sure to have something else to do while grinding out the appearances.
 * Floor 05 - CHUDO only has a single Hovering Tuber in a prison room. If you enter and exit the floor this will eventually be replaced with a Mk-1 Treasure Tuber. Farming Video: https://www.youtube.com/watch?v=IOHNPtUm7LY
 * Floor 11 - NOKEJIRI only has a single Hovering Tuber in a square grassy area with 3-4 other enemies in it. If you exit and leave the level via the escalators this will eventually be replaced with a Mk-2 Treasure Tuber.