This is a small but rather furious level.

Fight off enemies coming at you from everywhere in the dreadful and confusing outdoor area. Locate the Silver Key in the north-eastern part, but watch out for the mutants outside the columns. Health and powerups are found in the main section as well as behind a secret door in the south-western corner. Find the Gold Key at the eastern end of the corridor in the north. The elevator is in the opposite end of the corridor. More powerups and a 1-up are found in the two rooms in the northern part. But the fighting continues.