Enemies that feel deliberate

Design behaviour for an enemy that <describe what it should feel like
to fight>.

Use a small state machine — patrol, alert, chase, attack, retreat —
with explicit transitions. For each state: what it does, what makes it
leave, and what the player sees that tells them the state changed.

That last part is the point: the player must be able to read the
enemy's intent. Tell me the visual or audio cue for each transition.

Add a short delay on noticing the player and on losing them, so it
doesn't snap instantly between states.

Keep the numbers in a config object I can tune while playing.