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These are the features that are missing in some variants of The Immortal.

• the worm trap in the first room of the game
• the flame jets in the second room of the game
• the chest in the second room changes position based on which version of the game you're playing
• fireballs in levels one, three and five
• the map of the pit traps in level one
• the charm spell is found on the floor in level one in some versions, and in a chest in others
• the door in level one which connects the second room to the last one
• the second door connecting the large room to the one above it in level two
• the poisonous drink in level three
• the muscle potion in level three
• the infinite hallway in level three
• the second door connecting the two main troll rooms in level three
• the enemy attacking you at the beginning of level four
• the programmers' hallway in level five (sometimes replaced by an empty hallway with entrance near entrance to worm room), meaning you can't get the B.O. Bomb
• level six (the spider level)
• the sonic protection spell and its necessity in level eight (Mordamir's sonic attack is sometimes replaced by a lightning dud)
• the bones being thrown at your in level eight
• enemy fatality animations