Edens_zero_21_pro_acb.mkv Guide

Likely a shorthand for the release group's name or a specific audio/video codec configuration used for that file.

This episode concludes a major portion of the with the following key events: Edens_Zero_21_Pro_ACB.mkv

Often indicates a "Professional" or "Premium" encode, sometimes associated with specific release groups that prioritize high-bitrate video. Likely a shorthand for the release group's name

Shiki and Homura are forced into a fight with a massive ore creature called Black Rock. Rebecca and the rest of the crew arrive to assist, using concentrated firepower and Shiki's gravity powers to defeat it. Rebecca and the rest of the crew arrive

Despite defeating the creature to bring their "prisoner counters" to zero, Madame Kurenai reveals the counters were a lie and resets them to 100,000, intending to keep them enslaved.

The terms in your filename typically provide technical context used by fansubbing or encoding groups: Refers to the episode number.