No missable achievements (plus 16 unknown)
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Beat Ruins of Red Clay Room 1 without touching the Skull Switch.
Complete The Final Path.
Visit each room in the Prison of Agnus.
Beat Engine of Insanity Room 4 destroying all Reapers.
Beat The Darkest Pits Room 5 destroying all Reapers.
Beat The Crypt Room 5 without waking the Gargoyles.
Beat The Final Path Room 9 without destroying all TNT blocks.
Beat The Darkest Pits Room 4 without harming any Reapers.
Beat Lost City Room 5 destroying all reapers, but without disturbing the central stack of blocks.
Beat room The Final Path Room 1 without touching any switches or skulls.
Beat room Limestone Quarry Room 1 without activating any Skull Switches.
Beat Frozen Cavern Room 5 without touching any of the Skull Switches.
Beat Frozen Cavern Room 4 with 5 Ice Blocks remaining.
Beat room Electric Lab Room 3 without touching any of the top four switches.
Beat room Engine of Insanity Room 3 before the stone block falls to the floor.
Complete the Prison of Agnus in under 45 minutes.