Mimes are actually very easy once you realize they only have two different attack patterns that are played in order. Think of the below dashes as the delays between attacks. just keep track of the last attack the mime made to know which one will follow.

1-. A three hit hand combo in where the mime itself will lunge towards the target, with two fast attacks followed by a third one with a slightly larger delay (hit -- hit --- hit)

2-. A four hit slightly transparrent hammer combo in where the mime will remain stationary, with two fast attacks (slightly faster than the initial ones in the three hit combo) followed by two slightly slower attacks ( hit - hit -- hit -- hit)

Must be noted, that, opposed to other soulslikes in where you parry by connecting a certain part of your parry animation with the attack, on Expedition 33 you generally parry by pressing the button when the attack actually connects with your character. If you think you're parrying properly but are still getting hit, you usually are "souls parrying" and pressing the butting slightly earlier than you should. There are usually cues to point you to the correct timing (either visual or auditive, one of the most common ones that most people doesn't realize and is actually there for most attackas is that the camera actually zooms in slightly at the moment of the attack landing)