I've made this tutorial in my native language (Brazilian Portuguese), soon will be added subtitles so everyone can perfectly understand.

In the meantime, while i'm too lazy to add subtitles to the video, you can follow this text guide below:

For Klassic Tower Mode you have to play as Kotal Kahn (Blood God) as his variation has the most fast pace combination in the game, the strat you wanna do with him is:

Round 1 - Right off the bat, start with a Tonaltzintli + Crystal Totem, then run or dash to the opponent, another Tonaltzintli + Blood Offering, at this point you will have your opponent in the corner (except if you're playing on Dead Woods or any large size level) and Kotal Kahn will be incredibly powerfull, just uppercut your opponent 3 times and GG.

Round 2 - It should start with your opponent already in the corner, if so, you do Tonaltzintli + Crystal Totem, then Tonaltzintli + Blood Offering, Uppercut 1 time, then do Enhanced Sunstone + Uppercut w/ the opponent in mid-air, it saves 1 precious second compared to 3 uppercuts.

At the "Finish Him" moment you wanna do a back + 4 (fast sweep) to knockdown your enemy as fast as possible to proceed.

Also, there is important stuff to mention, some enemies can react (Wake Ups and in the worst cases, they will try to X-Ray you, which is reset point), but the biggest problem is, if at any moment you get a Jason (Unstopabble) on your tower, then just reset, because with this variation he gets ressurected at the end of round 2, so that's a 10sec-15sec time loss for nothing.