Those "bulls" usually does things like Attack Guard Break Attack Guard Break in an orderly manner, although not for certain. Things get trickier when they get skills to cast later on. They have unique names too (DESTOROYAH).
"I will send anything that interfere with my romance flying out of the Solar System!" - Saber in Fate/Extra
i hope this helps B > Break G> Guard A> attack Viper -baabb -bbaaba -bababa there 2 more attack patterns Crix -ggaagg -agaagg -gaaagg -ggaaag ClusterHorn -agbagb -gbagba -bagbag Rider its kinda Mix but some times the pattern goes like this but dont depend on this pattern much cause i told u its kinda mix due to spell combos and such -gagaga -bgbgbg
currently im at stage 2 this is all i could give u