Online moderation is apropos to community curation as a way to fight against malicious behaviors bristling on User‐Generated Content (UGC)‐based Social Network Sites (SNS). Given the current research gap on voluntary moderation from the perspectives of power misuse, we investigate how power abuse by a moderator would affect the community dynamics in terms of participation indicators, linguistic characteristics, and network structure in a computational fashion. An event on Reddit is chosen for a case study. Using interrupted time‐series analysis and social network analysis, we find moderation fueled short‐term feuds and brought potential prolonged destruction to the community. People's linguistic patterns remained stable while the liberation from “tyranny” brought the community back to life and the power competition entailed negative repulsion. We also find an “Exodus” phenomenon as netizens voted with their feet and migrated to a mirror community when facing severe moderation. This preliminary research expands the connotation of moderation by addressing more forms of power abuse. We also refer to social movement and community choice theories in relevant fields and provide the insights of online moderation from interdisciplinary perspectives.