-ActionController must know when active_actor enters a threatened square, and which creature(s) are threatening
-must know when the actor leaves a threatened creatures' threat square, and if the creature is still a threat
-prompt the user before movement, if they confirm movement they may provoke OA
-if OA is provoked, ActionController must temporarily allow the provoked creature to React
-prompt the user if they wish to react and perform an Opportunity Attack and spend their reaction for the turn
-execute and resolve the OA if it is performed
See #26, #21, #7, #6
-ActionController must know when active_actor enters a threatened square, and which creature(s) are threatening -must know when the actor leaves a threatened creatures' threat square, and if the creature is still a threat -prompt the user before movement, if they confirm movement they may provoke OA -if OA is provoked, ActionController must temporarily allow the provoked creature to React -prompt the user if they wish to react and perform an Opportunity Attack and spend their reaction for the turn -execute and resolve the OA if it is performed