What's a State Alias in Unreal Anim BP?

A virtual state that represents a set of source states for transition rules. Lets you write 'from any of these locomotion states → jump' without N transition lines from each state.

Why doesn't my alias trigger?

Open the alias node. The States list must contain at least one source state. If empty (the default), no source matches and the transition never fires.

Rule returns true but no transition?

Check transition priority order; another transition may consume the rule before the alias's. Right-click transition arrow → Set Priority Order.

Fix: Unreal Anim BP State Alias Won't Transition

Quick answer: Open the State Alias node. Populate States with the source states it should represent. Confirm the rule node and check transition priorities.

Locomotion BP. Want a Jump transition from Idle, Walk, or Run. Add a State Alias, draw the transition. Press jump. Nothing. The alias has no source states selected.

The Symptom

Transition rule evaluates true (you can verify with print) but the state machine doesn’t move.

The Fix

State Alias node (Locomotion):
  Details panel:
    States:
      ✓ Idle
      ✓ Walk
      ✓ Run
      _ Crouch    // excluded

Transition: [Locomotion alias] → [Jump]
  Rule:
    Get bool: bIsJumping
    Return Value

States list is the meat of the alias. Empty list = matches nothing. Tick the source states that count for this transition.

Priority Order

If multiple transitions share a source, Unreal evaluates by priority. Right-click the transition arrow, Set Priority Order. High priority wins. Your alias transition may be losing to a more-specific transition with the same rule.

Verifying

Set bIsJumping during Idle / Walk / Run. Each transitions to Jump. Crouch (excluded) doesn’t.

“Alias states populated. Rule simple. Priority correct. Transition fires.”

Related Issues

For BP replication condition, see replication. For PostProcess alpha, see postprocess alpha.

Tick the states. Alias matches. Transition fires.