Felix watched as Nemo took position at the side of the door. Felix briskly walked over to the front of the door and cleaved the thick steel with two slashes, carving a cross into the thick metal. Because of the perfection of the cuts, and the fact that the door weight thousands of pounds, the door did not crumble on the spot, which is what Felix was banking. Within a second of making the cuts, Felix punched the door at where the cross lines intersected with his manaegis gauntlet. 

The manaegis did not make Felix physically stronger. Felix was in good shape, but not enough to move thousands of pounds with a punch. The ethereal material that manaegis is made from, aptly dubbed Manalloy by Felix, is a special material with special properties. First off, normal physical matter is incompatible with Manalloy. This makes the makes contact between the two repellent in nature. This makes jumping much easier, and makes much more force from impacts cause more devastation. The other special property is that manalloy, once formed into the solid manaegis, can not have its form changed. This makes it impossible to scratch, dent, or bend manalloy. Instead, every time manalloy receives certain damage, the mana that is used to create begins to slip away into mana waves. Once it has received enough damage, the manalloy evaporates into mana. This can be used in many ways but is the reason why Felix's sword can cut through things with such ease. Felix has willed the the size of the blade edge to be an atom thick. Because of the fact that manalloy can not lose its form once made into manaegis, the blade retains its shape and does not crumble. This allows Felix to separate the molecular bonds holding the steel door together. This only works on items that aren't charged with mana or made from mana. If Felix were to, say, attack an enemy who was using an enchanted weapon, the weapons would clash harmlessly. This is due to the fact that manalloy is made from mana energy, and a weapon enchanted is infused with mana energy, the physical properties of mana energy counteract with each other resulting in a repelling force of which is equal and opposite to the energy used to propel the weapons forward. 

Once Felix's fist came in contact with the door, the steel fell apart in a loud grinding screech. As soon as the door fell apart, Felix hid to the side, letting Nemo take it from here.

The guards quickly turned to face the crumbled heap that was the cell door. The darkness from inside the cell, in tandem with the light from the hallway made it very difficult to see anything from the cell except pitch black. 

"Hey... this is Xero the Devourer's cell isn't it?" The guard on the left said to the guard on the right in Italian. It was clear they were both Italy natives, or just lived long enough at the Vatican that it became second nature to speak the language. 

"Yeah... they say he kills people by eating their souls." The guard on the right said shakily. "Say... didn't you say the other day that you are better at seeing in the dark than me?" Guard Right pointed out, "maybe you should take the lead."

"Screw you man, I have a wife and kids. You are the single virgin here. You take the lead" Guard Left hissed.

Too afraid to enter, both guards leaned in as close as they dared to inspect the cell.