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Gen cast maps to to essentially castout anad castoutlp, which has a maximum of 90 frames / 3 seconds in spells.2da. Consider splitting out c_x_gen_cast out so that the first half provides the castout FNF animation and cast event, then take about 5 frames after and copy paste/reverse them so you create a seamless loop (copy paste on dope sheet, press S and the "-1" to reverse); make the end of your loop matches the start or you will hitch; this will be at a really shakey speed, so then on the same seemless seamless loop scale it slower by pressing "S" and then "4'.
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