To handle loops I believe most implementations have a &quot;restart on complete&quot; flag on trees or nodes. So if the first node was a sequence node you could set it to start back at the first node after the last is done.<p>There&#x27;s a second post that may answer some of your other questions. &quot;Advanced Behavior Tree Structures&quot; <a href="https:&#x2F;&#x2F;gamedevdaily.io&#x2F;advanced-behavior-tree-structures-4b9dc0516f92#.djupivlag" rel="nofollow">https:&#x2F;&#x2F;gamedevdaily.io&#x2F;advanced-behavior-tree-structures-4b...</a><p>Unity has a decent behavior tree plugin called Behavior Designer. I&#x27;ve only used it a tiny bit so I&#x27;m still getting a grasp on what it does and does not handle well. Poking at it, or simply it&#x27;s documentation, may also help. <a href="https:&#x2F;&#x2F;www.assetstore.unity3d.com&#x2F;en&#x2F;#!&#x2F;content&#x2F;15277" rel="nofollow">https:&#x2F;&#x2F;www.assetstore.unity3d.com&#x2F;en&#x2F;#!&#x2F;content&#x2F;15277</a> <a href="http:&#x2F;&#x2F;www.opsive.com&#x2F;assets&#x2F;BehaviorDesigner&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.opsive.com&#x2F;assets&#x2F;BehaviorDesigner&#x2F;</a>