The moment Lex set his first step onto the second floor a couple of things happened. First, some esoteric knowledge about how using appropriate forms while punching produced different results appeared in his head. Second, his intuition started blaring about incoming danger.
But by now Lex had become fairly used to emergencies. His reaction was quick yet smooth, and lacked the jerkiness that came with dodging an unexpected attack.
He leaned forward just enough to dodge a paper thin blade that had aimed to slice through the back of his neck. The fact that Lex felt the need to dodge meant that the blade was sharp enough to cut through his defenses.
Calmly he moved his hand forward and transitioned from leaning forward into a single-armed handstand, allowing him to look back. A strange looking creature had attacked him, and was preparing to attack again after its ambush failed. It was bipedal but with four arms, two coming out from its shoulders but two coming out from its back.