In the clip above, you can see Tyson coming in with a jab whilst changing levels. He moves his head to the right and approaches behind the jab.
This way, Tyson is able to transmit his weight over to the other side of the body.
It allows him the freedom to shift his weight back whenever required with a right hand over the outstretched arm of Frank Bruno.
The second major thing you see in the clip is no different from his trademark slipping a jab from the outside and then moving inside with an overhand right.
As Tyson came in, he changed his head direction and moved towards the right and came up with a jab of his own.
Everything he did primed his right hand and all he had to do was to shift his weight back over to the left by throwing an overhand right.
In situations, where Tyson wasn’t able to find an opening for an overhand, he would quickly readjust levels to land a left hook.
Doing so from a cross position made the move unpredictable and caught his opponent on a blindside. Throwing left hook whilst changing levels always works wonders against tall fighters.