This one can be found right before you enter the first door in Mission 7. It is at the right where there is a ledge above and it is represented as a red glowing candle-like structure. In this mission, you are required to stay in air for 20 seconds.
For first timersEdit
Wedge yourself into a corner and let the enemies approach you. When one of the enemies try to scythe you, quickly jump and jump again ABOVE their heads. Then, when you are at the topmost level of your jump, quickly perform an air attack with your Style button. Swing and Aerial Cross are not advisable, since they are too quick and can knock enemies back, resulting fewer heads to jump off. Then, when you are about to land on one of the enemies heads, quickly jump again and perform another air attack. If the enemies jump too, good for you because then you will jump higher. Do this over and over until 20 seconds is up.
If you are experienced with Jump Canceling, you can use that as well to stay in the air, but also use other strategies, since the Hell Prides can't take enough punishment to last the whole time. Air Hike is also helpful.
For experienced fightersEdit
If you have Air Raid, max out your DT gauge and perform Air Raid without being attacked by jumping enemies.
Trickster's Wallhike coupled with Enemy Steps can also allow you to stay in the air for sometime, and is particularly useful as it does not require you to damage any enemies.
Do the same, but use Aerial Rave with your Yamato instead.
Not much of an easter egg but for unexperienced/no one who has ever played DMC3 or even know who Nevan is, this Secret Mission exploits the later obtainable weapon Nevan on Dante's back as the equipped weapons on the Mission Start Menu.