For the sake of this every character that I am writing about is alive during this time period and this is basically your reaction/what you are doing in the events of Episode 81
Niccolo: You were terrified to say the least as you looked around for Niccolo trying to figure out where he had gone and if he was safe
Porco: You were confused to what was going on but you were fighting in order to protect everyone around you alongside Porco
Pieck: You and Pieck worked with soldiers to try and save people
Zeke: You were panicked because you thought that this was not the plan when it was clear Zeke had no control
Colt: You were worried about what your brothers had done as you and Colt ran through the streets looking for his brother
Annie: You were fighting and then started to make your way to where her crystal form was kept when you heard what was going on
Reiner: You stayed with him the whole time making sure he was ok and cleaning up the blood on his side
Bertholdt: You both were looking for your friends neither of you bothered to transform as it would probably slow you both down.
Yelena: You were more confused than she was but listened to Yelena when she told you not to panic