✅ Murmur ap cost fused as bottom

Category	Ability
Status	Passing
Test	tests/test_abilities_passive.py::test_murmur_ap_cost_fused_as_bottom

Murmur fused as bottom card — the top card inherits Murmur's -2 AP Cost.

Preconditions

• Lane 0: P1's fused demon — top=Duban (#001), bottom=Murmur (#002)

• Murmur passive: -2 AP Cost

Action

• Query get_effective_ap_cost(state, fused_demon, base_cost=2)

result = get_effective_ap_cost(state, fused_on_field, 2)

Expected Postconditions

• Returns 0 (2 base - 2 from Murmur bottom card = 0)

Assertions

assert result == 0, f"Expected AP cost 0 (Murmur bottom passive), got {result}"