It seems like you are referring to the relaunch combos. What you must do is do a pop up (launcher) combo and then jump as they arch in the air, right before they land you have a small window to connect another jump punch that fools the game into thinking they are on the ground, making them stand up and sell the attack standing instead of being juggled. If you mistime it, they will either be juggled by the jump punch, missed, or they will be able to block it.

This is the predominant falling unblockable frame in which you have to hit them in order for a relaunch to be unblockable:

Which is slightly different than the first blockable frame:


For some reason at the end of an autocombo, you cannot block on this frame, or even completely lying on the ground which is why you can sweep after Jade's and Kitana's 4 hit punch combos and Jax's 7 hitter (minus the the last hit). Nightwolf has a 3 hit kick combo and the first hit is very low to the ground, allowing him to hit the Robots, Kabal, Kano, and Sheeva while they are laying completely on the ground in the corner within the duration of time you have before they can block. In any other situation, if you hit someone while they are lying on the ground, or in the first landing/blockable frame you will instantly appear blocking if holding block. If you connect a standing LK or HK after an auto combo the opponent will appear standing and selling the hit, unable to block.

Getting back to relaunch combos, not everyone can relaunch every character due to collision detection. Kano, Ermac and Human Smoke can relaunch everyone, Sonya Kabal and Classic Sub-zero can relaunch a lot of characters, and so and so forth. Some characters are very hard to relaunch, some are easy when it's the computer, like the Robots and Sheeva, because they don't block until the combo breaks and their vertical collisions are taller than others. This means they are touching the ground and still hittable for longer duration, but they are in blockable frames longer as well, so ultimately they have just as small a window to legit relaunch.

this was a very helpful turtorial. i thank you for your time good sir. your obviously a highly respected and experienced warrior both in the mk universe, and in the ring. i thank you.

Thanks man, I like to think of it that way. I assume you have checked out my wrestling stuff then?

i have and i enjoyed it a lot. im an artist myself, so i use my talent to help promote some of the wrestlers that perform around my area. its really great seeing people keep the good times alive.