E3M8: D'Sparil's Keep (Heretic)

E3M8: D'Sparil's Keep is the eighth level in The Dome of D'Sparil episode of Heretic.

Walkthrough
You start in a water area, with various Gargoyles around you. In the corners of the pool, there is an Ethereal Crossbow, some Ethereal Arrows, a Shadowsphere, Wings of Wrath and a Silver Shield; collect them if you need them, then fly to the higher area, collect the pair of Lesser Runes, and you should notice a wall slightly different from the others, that isn't scrolling. Open it; the secret behind contains a Tome of Power, a Bag of Holding, a Quartz Flask and a Chaos Device. Now enter the opened portal. You will land in a small room with a pair of Disciples of D'Sparil, and cover. Blast them and pick the Dragon Claw and the Energy Orb, as well as two Crystal Vials and any Claw Orbs the Disciples may drop. Now go back through the portal. Enter the newly opened one in the main room, but make sure to activate your Shadowsphere before. You'll land in a room filled with Nitrogolems. Among them there are Gauntlets of the Necromancer, Ethereal Arrows and a Claw Orb. Use either the Dragon Claw or the Gauntlets to get rid of them. Now go back to the main room and enter the third portal. Three Ophidians will greet you. Destroy them and grab the pair of Lesser Runes, and activate both switches. An Iron Lich will be your new obstacle. Behind him, the Hellstaff, Crystal Vials and Greater Runes, as well as the portal. Suggestion: activate your Tome of Power and blast the Lich with the powered Crossbow. This should finish him before he has time to deal any significant damage. Back to the main room, enter the last portal. You'll land on a trident-shaped ledge, with a Tome of Power, an Enchanted Shield and a Phoenix Rod. You'll notice D'Sparil and his Green Chaos Serpent below you poised to attack...

When the Serpent Rider dies, a passage with a switch will open at the far end of the arena. Then, stairs will rise to the exit portal. Congratulations, and enjoy the ending.