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During Test Your Metal occasionally one of the enemies AI just breaks. At the start of the match, you can see them stand up straight, and simply stand there, letting you beat them down. They kind of hover around, and you can sometimes see them flare up with unblockable runes, and counter runes, but still all they do is stand there.
I've seen this in the general world as well, where a Zealot I was having a hard time against, suddenly 'broke', just standing there to let me kill them. For such a tough fighter to just glitch out and stand idle kind of takes the joy of beating a tough opponent, for obvious reasons.
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