With Mission 18, we’re finally done getting all collectibles included in Dmc – Devil May Cry: the last two missions are boss fights and as such they don’t have anything to collect. If you have been following our guides up to this point and you have collected every lost soul and secret door key, as well as opening all the doors, after you are done with this mission, you’ll also get a Trophy/ Achievement for obtaining a 100% completion rank in all missions. The 100% is an absolute necessity if you’re aiming to get another Trophy / Achievement, awarded to all gamers who manage to complete all missions on the Nephilim difficulty mode with a SSS Rank. With the game being almost generous with Style Points awarded during battles, with the 100% completion rate multiplier you won’t have any problems getting the SSS rank for all missions. The lost souls, key and door of this mission won’t be a problem at all since they’re easy to reach and sometimes even easier to reach.
Mission 18 – Demon’s Den
Lost Soul 1: Enter the first tunnel to the left, the one close to the small central one with the recovery star: once you reach an opening in the ground look carefully to see a ledge. Jump down on the ledge and proceeed to get the lost soul.
Lost Soul 2: In the middle area of the tunnel to the right of the generation in the main area you will find the lost soul to the left: just look around once you start hearing the noises and you will locate it with ease.
Lost Soul 3: Get into the tunner to the left of the generator: proceed to hear the lost soul noise and look below. You will find a platform: jump on it, free the lost soul and you will be done with all of the lost souls.
Argent Key: Get into the right tunnel from the generator and keep going until you reach a hole in the ground: jump down and to the left and then proceed onwards to get your arget key
Argent Door: This door is pretty hard to miss: in one of the tunnels you will reach a big area with a few platforms. The Argent Door is in plain view. This big area is in the tunner directly to the left of the generator.
Article from Gamersyndrome.com