Conduits serve as a more advanced and sharable transition resource. Where a Transition Rule is going to be a simple 1-to-1 relationship form one state to another, a Conduit can have 1-to-many, many-to-1, or many-to-many.
Conduits appear on the graph and look similar to a State but have a different icon preceding the Conduit's name (below).
An example use case for a Conduit could be a situation where you have multiple animations that could play when a character is killed.
You could start with a simple Transition Rule that says when the health of that character is less than or equal to 0, then go to a Death state. However, if instead of a State, the transition went into a Conduit, you could perform a series of checks to see how the player was killed (shot, stabbed, explosion, hit by a car, anvil on the head, etc.) and branch from there into various independent death States.
A simplified version of that graph may look something like below:
Inside, a Conduit graph looks just like a Transition Rule:
The actual transition rules that exit the Conduit can then determine the type of death and allow blending to the appropriate state.