✅ Morax fused with murmur nurture costs 0 ap

Category	Ability
Status	Passing
Test	tests/test_abilities_passive.py::test_morax_fused_with_murmur_nurture_costs_0_ap

Tests interaction between Morax, Sabnock.

Preconditions

• P1 Main Phase, P1 has 3 AP

• Lane 0: P1's Morax (#006) fused with Murmur (#002)

• Fused HP = 12 + 3 (fHP) = 15

• Fused PWR = 4 + 2 (fPWR) = 6

• Murmur passive: -2 AP Cost (active as bottom card)

• READIED

• Lane 0: P1's ally demon — 15 HP, 10 damage, READIED

Action

• Morax-Murmur casts Nurture (ability[0], Quick, 1 AP, ready, 1x)

• Effective AP cost: max(0, 1 - 2) = 0 AP

• Nurture heals target by PWR = 6

from engine.abilities import execute_ability
    from engine.operations import get_effective_pwr, get_effective_ap_cost
    import importlib
    import engine.abilities_actions
    import engine.abilities_passive
    importlib.reload(engine.abilities_actions)  # force re-registration after fixture clear
    importlib.reload(engine.abilities_passive)

    # Create fused Morax (top) + Murmur (bottom)
    fused = make_fused_demon("006", "002", lane=0, owner=Side.PLAYER_1)
    ally = make_demon("003", lane=0, owner=Side.PLAYER_1, damage=10)  # Sabnock as ally

    state = make_game_state(phase=Phase.MAIN, current_player=Side.PLAYER_1)
    state.players[Side.PLAYER_1].ap = 3
    state = place_demon(state, fused)
    state = place_demon(state, ally)
    fused_p = state.demons[0]
    ally_p = state.demons[1]

    # Verify fusion stats
    pwr = get_effective_pwr(state, fused_p)

Expected Postconditions

• P1 AP: 3 (unchanged — Nurture cost 0 with Murmur's -2 AP)

• Ally damage: 4 (was 10, healed 6)

• Morax-Murmur: still READIED (Nurture has ready_required, does NOT exhaust)

Assertions

assert pwr == 6, f"Fused PWR should be 6 (Morax 4 + Murmur fPWR 2). Got {pwr}"

    # Verify effective AP cost of Nurture (ability[0], base cost 1)
    effective_cost = get_effective_ap_cost(state, fused_p, 1)
    assert effective_cost == 0, f"Nurture should cost 0 AP (1 - 2 = 0). Got {effective_cost}"

    # Cast Nurture targeting ally
    result = execute_ability(state, fused_p, ability_idx=0, targets=[ally_p])

    # AP unchanged — cost was 0
    assert result.players[Side.PLAYER_1].ap == 3, (
        f"AP should be 3 (Nurture cost 0 with Murmur's -2). Got {result.players[Side.PLAYER_1].ap}"
    )

    # Ally healed by fused PWR (6)
    ally_after = next(d for d in result.demons if d.instance_id == ally_p.instance_id)
    assert ally_after.damage == 4, (
        f"Ally should have 4 damage (10 - 6 healed by PWR). Got {ally_after.damage}"
    )

    # Morax-Murmur still READIED (ready_required does NOT exhaust)
    fused_after = next(d for d in result.demons if d.unit_id == "006")
    assert fused_after.state == DemonState.READIED, (
        f"Fused demon should still be READIED (Nurture uses ready, not exhaust). Got {fused_after.state}"
    )