These are listed in reverse order. I will continue to update as I go back and record the rewards and challenges for each tower.

Note: Any stages with Test Your Might can vary on payout. I am using the maximum I've earned on Test Your Might to calculate totals. Your mileage may vary.

Tower 33
3 Energy per fight
6 Fights
7590 Koins
Must use D'Vorah – Venomous Level 35 Gold character
Boss Kotal Kahn Sun God at the end. He's tricky but not insurmountable. Watch out for when he uses reflect damage. Try to just block his attacks as much as possible. He's a good one to use the Monk trick on if you can spare the slot. He'll drop a shield early as well. Best tactic is to bring a character that has some sort of damage over time attack like Reptile's venom.

Tower 32
2 Energy per fight
5 Fights
6100 Koins

Tower 31
2 Energy per fight
5 Fights and 1 Test Your Might
7475 Koins

Tower 30
2 Energy per fight
5 Fights and 1 Test Your Might
8750 Koins

Tower 29
2 Energy per fight
5 Fights and 1 Test Your Might
7231 Koins
Boss Sub-Zero at the end. He has the ability to use Ice Armor which protects him from most damage. He'll still take some damage but really it's just waiting until the ice armor wears off and hammering him when it's down.

Tower 28
2 Energy per fight
5 Fights and 1 Test Your Might
8550 Koins

Tower 27
2 Energy per fight
6 Fights
6870 Koins

Tower 26
3 Energy per fight
6 Fights
6090 Koins
Must use Kenshi – Balanced Level 30 Gold character
Boss Ermac at the end. Only Kenshi or Bronze characters can hurt him, but the good news is that any Kenshi character can hurt him. Ermac is annoying with a combo that can drain power. Use the Monk trick here to good effect and take advantage of the Kenshi character they give you. However, even if you have a silver Kenshi at a decent level this fight may not be that tough.

Tower 25
2 Energy per fight
6 Fights
5970 Koins

Tower 24
2 Energy per fight
5 Fights and 1 Test Your Might
5950 Koins

Tower 23
2 Energy per fight
5 Fights and 1 Test Your Might
5828 Koins

Tower 22
2 Energy per fight
5 Fights and 1 Test Your Might
5706 Koins
Boss Quan Chi fight at the end. He is flanked by two fused and levelled Oni that aren't that tough but will continue to respawn at full strength as long as Quan Chi is standing. Beat down the Oni until Quan Chi steps in and hit him with everything you've got. The Monk trick talked about in Tower 19 will work here if you have a gold character at level 20 with an X-Ray attack.

Tower 21
2 Energy per fight
5 Fights and 1 Test Your Might
5584 Koins

Tower 20
2 Energy per fight
6 Fights
5370 Koins

Tower 19
3 Energy per fight
6 Fights
4590 Koins
Must use Quan Chi – Warlock Level 20 Gold character
Boss Kung Jin at the end. His wind attacks are supposed to be powerful but your best bet is to take a Monk. Get Quan Chi's Special 2 charged up and then drop in the Monk. Let Kung Jin take out the Monk and then tag-in Quan Chi and have him use his X-Ray Attack. That's it!

Tower 18
2 Energy per fight
6 Fights
4470 Koins

Tower 17
2 Energy per fight
5 Fights and Test Your Might
4425 Koins

Tower 16
2 Energy per fight
5 Fights and Test Your Might
4303 Koins
Boss Scorpion at the end. He can be really tough and the best way to beat him is with Spec Ops cards. At the very least you will need two Silver cards levelled up to no less than 22 but 30 each would be better. Another tactic would be if you have a Gold card at least at level 20 that is also Spec Ops. He hits for high damage so be sure to go defensive but attack whenever you can. This can be a tough fight and makes Reptile seems easy.

Tower 15
2 Energy per fight
5 Fights and 1 Test Your Might
4181 Koins

Tower 14
2 Energy per fight
5 Fights and 1 Test Your Might
4059 Koins

Tower 13
2 Energy per fight
6 Fights
3870 Koins

Tower 12
3 Energy per fight
6 Fights
3090 Koins
Must use Kitana – Assassin, level 17 Gold character
Boss Reptile at the end. Take advantage of Kitana's ability to damage on a tag-in by tagging her out at the beginning of the fight. Characters with drain powers will be useful as well. The trick is to think defensively, take advantage of Kitana's ambush ability and drain attack, and hit with anyone else who has drain attacks. He can take out Kitana quick so be mindful when she is tagged in.
Also worth noting that this is the first tower that costs 3 energy per fight. Something to consider as you start.

Tower 11
2 Energy per fight
6 Fights
2970 Koins
Decent for farming even later in the game just because the payout vs. effort is decent. Use this for some levelling/farming on lower characters. This and Tower 10.

Tower 10
2 Energy per fight
5 Fights and 1 Test your might
2900 Koins
Boss Kotal Kahn at the end. A decent team should beat him easily, but be prepared to go defensive as he can hit for a lot of damage.

Tower 9
2 Energy per fight
5 Fights and 1 Test your might
2778 Koins

Tower 8
2 Energy per fight
5 Fights and 1 Test your might
2656 Koins

Tower 7
2 Energy per fight
7 Fights and 1 Test your might
3764 Koins
Oddball tower with 8 stages overall! Be prepared with 2 teams to clear or be forced to wait for energy to replenish.

Tower 6
2 Energy per fight
6 Fights
2370 Koins
Significant jump up in payout from Tower 5, first tower worth farming but needs multiple teams due to the number of fights.

map01 Tower 5
2 Energy per fight
5 Fights and 1 Test Your Might
1375 Koins total
Must use Sonya Blade – Demolition (Level 6 Gold) and prevent her from being KO'ed
Boss Kano at end (Easy fight)

Tower 4
1 Energy per Fight
5 Fights and 1 Test Your Might
1253 Koins total
Last tower with 1 energy per fight. Still my favorite place to complete Daily Bonus Missions if they won't happen by just naturally playing the game.

Tower 3
1 Energy per Fight
5 Fights and 1 Test Your Might
1131 Koins total

Tower 2
1 Energy per Fight
5 Fights
700 Koins total

Tower 1
1 Energy per Fight
2 Fights
90 Koins total
Essentially not worth bothering with once you've beaten it.