Technique Mimicry

Technique Mimicry is the ability to copy techniques and/or skills of another.

Overview
Users of this ability can replicate the techniques and/or skills of those whom they've fought against or witnessed in the heat of battle; this can have varying degrees of success, with some individuals being able to mimic them perfectly whilst others can only produce lackluster copies.

The results of mimicking a skill can depend on a number of different factors, such as the potential of the copier or whether the original user performed said technique at its highest level.

Garou
Garou is capable of memorizing an opponents movements thereby allowing him to copy their fighting style after only seeing it once, such as when he replicated Watchdog Man's moves to an unknown extent and utilized them against Genos during their battle or when he managed to use Bomb's Whirlwind Iron Cutting Fist against Royal Ripper after only seeing it once; albeit he could only perform a lesser variation of it at first. Nevertheless, being a prodigy in martial arts as well as overcoming a near suicidal degree of training by thrashing entire dojos and hunting down heroes, Garou improved Bomb's fighting style to a level where he could use the Cross Fang Dragon Slayer Fist alone when it normally requires two fighters working in tandem in order to function. After being mutated by "God" and achieving his Cosmic Fear Mode, Garou's ability to replicate fighting styles has been enhanced to where he's capable of even duplicating the S-Class Rank 1 hero, Blast's abilities to create portals and manipulate gravity during their short exchange.

Orochi
Orochi, who's a combat prodigy in a similar vein as that of Garou, has demonstrated himself to be capable of perfectly copying Garou's Water Stream Rock Smashing Fist after only briefly glancing it once during their fight. He can utilize this martial arts just as well as the Hero Hunter.

G5
G5 has also shown itself to have copied Atomic Samurai's signature technique, Atomic Slash. However, his version of the attack was of a much lesser extent compared to that of the S-Class hero's and, as a result, G5 lost his battle against the swordsmen.

Saitama
In his fight against Awakened Garou: Cosmic Fear Mode, it's revealed that Saitama possesses the ability to learn and master any techniques or powers of his opponents just by witnessing them once, being similar to but even better than Garou himself. This means that should Saitama so wish, he can grasp and master any martial arts instantly, despite him being unironically regarded as an "amateur" by others on several occasions. He has shown the capability to copy not only Garou's extremely advanced martial arts but also his more supernatural abilities such as time travel.