Alternate Stage Four (hereby referred to as Stage 4') is titled "Fortress of the Water Dragon." There are two ways you can access this stage, but both require you defeat the Sanskrit beholder, Dogether.

The first path is through Stage 3, and it's easier to access as Richter. Proceed normally and don't let the Medusa Heads knock you down below. When you get to the giant golden skeleton (Paranthropus), defeat it and collect the Pot Roast that falls from below. The door will unlock and allow you passage into a misty cavern. Ghosts and Spear Guards will be plentiful. Take the Axe subweapon as Richter to reach Dogether's room. After the final Spear Guard, there will be a normal candle, and shortly after, a Subweapon Thief. Don't let him steal the Axe, or you'll have to do the level again. It takes three hits for the Thief to die. Once he's dead, stand on the left hand platform you find near the door. Turn right, jump and throw an Axe at the rock stuck at the top of the right hand platform's pulley. Hit it three times and wait on the left platform. You'll be brought to a small room with a candle and the door to Dogether.

The second path is through Stage 3'. After rescuing Sister Tera, destroy the Blood Skeleton pillar and fight the Grave Keeper. Defeat the Skeleton and ascend the stairs. Defeat the three stacked Bone Pillars and strike the chain or gear above the first spiked ball. When it detaches from the chain, fall into the hole on the right of where it used to be. Fall down the hole it made in the lower floor, but approach it from the right. There will be the spiked ball and a door to Dogether.