Probably the fact that he never does his time chucking bit unless he's already safely on another plane of time from his victim. Any other fight he was in where he had the opportunity, he didn't. Could have done it against Supes. Nope. Could have done it against the Legion (which would have made sense, if he wanted Supes to himself in order to hurt him). Nope. Could have done it to Prime, when Prime was yelling about how he was going to punch his face off. Nope.
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We are thought, and reality, and concept, and the unimaginable