The Nightmare of Ashihama is an interesting boss with quite a few unique mechanics. First of all, the Nightmare focuses attacks on the player with the highest melee defence, meaning it might make sense for your group to assign a main tank. Nightmare also attacks with all three combat styles, hitting through prayer although protection prayers do mitigate some of the damage.

The fight has 3 phases in which she will use different attacks.

Magic attack – Nightmare spins around releasing what look like pink petals. Use Protect from Magic.

Ranged attack – Nightmare twists backwards and then untwists, releasing a projectile. Use Protect from Ranged.

Melee attack – Nightmare flings her arms forwards and upwards, and then down in front. Use Protect from Melee.

Totems – At the end of each phase, you want to swap to your magic gear and attack / kill each totem with magic. Once all 4 totems are dead they will deal the final blow to Nightmare, activating the next phase. Once the next phase starts – many sleepwalkers will spawn. You should kill them with blood barrage.

Phase 1 – start attacking immediately and pay attention to Nightmare’s standard attacks in order to use the correct protection prayer. She will use the following special attacks during this phase:

• Flower Power – Nightmare will split the room into four quadrants, with only one of the quadrants being a safe zone – indicated by the green flowers. Standing in any of the other 3 quadrants will cause you to take damage and heal the boss.
• Husks – Nightmare will spawn two husks to attack random players. The husks will freeze players, preventing them from moving while attacking with melee. Use protection from melee.
• Grasping Claws – Nightmare will spawn many black portals and reach through them. If you’re standing on a black portal square you will take upto 50 damage.

At the end of the phase, kill all 4 totems with magic and be ready to blood barrage the sleepwalkers.

Phase 2 – Pay attention to Nightmare’s standard attacks in order to use the correct protection prayer. She will use the following special attacks during this phase:

• Parasites – Nightmare will throw parasites onto random players, which then grows and bursts out of the player, causing damage and healing the Nightmare. Players with a parasite should drink a dose of Sanfew Serum or Relicym’s Balm to weaken the parasite.
• Curse – A pink mist will fill the players screen, indicating that your protection prayers have now been switched.
  • Protect from Melee now activates Protect from Magic
  • Protect from Missiles now activates Protect from Melee
  • Protect from Magic now activates Protect from Ranged
• Grasping Claws – Nightmare will spawn many black portals and reach through them. If you’re standing on a black portal square you will take up to 50 damage.

At the end of the phase, kill all 4 totems with magic and be ready to blood barrage the sleepwalkers.

Phase 3 – pay attention to Nightmare’s standard attacks in order to use the correct protection prayer. She will use the following special attacks during this phase:

• Spores – Small spore-like things will appear, grow and burst from the ground, damaging any player in the surrounding area. Do your best to stay clear of the spores as they burst or you will take damage, run will be de-activated and your attack speed is slowed.
• Teleport Charge (aka Falcon Punch) – You will be teleported to one side of the room while Nightmare gets ready to charge straight ahead. Anyone caught in the charge will take up to 60 damage.
• Grasping Claws – Nightmare will spawn many black portals and reach through them. If you’re standing on a black portal square you will take up to 50 damage.

At the end of the phase, kill all 4 totems with magic and be ready to blood barrage the sleepwalkers.