In all nodes where a Task (action or condition) can be assigned, it doesn’t mean that only one task is possible to assign to that node. Multiple tasks can be assigned if you want to, and when you try to assign more than one task, NodeCanvas will automatically insert a task list; either an Action List or a Condition List accordingly (which are basically Tasks themselves).

Action List

An Action List has controls to reorder the actions inside, delete them, as well as disable some of them if you need to. An Action List can be set whether its actions run in Sequence or run in Parallel.

• Actions Run In Sequence. Actions will execute in order one after the other. The Action List will finish in Success when the last action is finished, unless an action finish in Failure in which case the Action List will immediately finish in Failure as well (thus the rest of the actions below the failed action will not execute at all).
• Actions Run In Parallel. All actions will execute at the same time. The Action List will finish in Success when all actions are finished, unless an action finish in Failure in which case the Action List will immediately stop all action still running (if any) and finish in Failure as well.

When set to run in parallel, you can also time the actions in a mini sequencer editor which lets you orchestrate the execution of the actions more precisely. In the example below there is a tween position and a play audio clip action, where the audio clip is placed to play while the tween is happening, but neither at the start nor at the end of it, but rather somewhere inbetween. Moreover there is also about 1 second delay added before all this.

The length of the actions only show for those actions that are deterministic in how long they take (like the tween above and the play audio if it was set to Wait Until Finish). If you create custom actions you can override the ‘length’ property to return how long your action takes. Regardless, the length is only informational and does not affect the execution of the actions in any way.

Condition List

A Condition List has controls to reorder the conditions inside, delete them, as well as disable some of them if you need to. As with all conditions, it can also be inverted. A Condition List can be set whether all conditions need to be true (AND), or any condition suffice (OR) for the Condition List to return true.

• All True Required. The Condition List will return true if all its conditions return true, otherwise it will return false. Thus in this case all conditions are checked.
• Any True Suffice. The Condition List will return true as soon as any condition returns true (thus the rest will not be checked), otherwise it will return false if all conditions are false.

Both Action Lists and Conditions also have two extra options in their “gear” menu, for saving the list as a preset file, as well as of course load a list from a preset file.