How do you get a DarkTyranmon?

In Digimon dusk how do you get Blackagumon to level 21?

I suggest putting him as a backup in your party and going to a strong place (any strong place would do) This is a good way to do this, but those who picked the attack group with the SkullGreymon in it, once the purple blob thing changes your digimon to Rookie rank, your SkullGreymon will be turned into a BlackAgumon. Now, if you want to digivolve into a DarkTyranmon (shown as DKTyrnmon and is highly suggested) even though you have all the dark skill needed, you still have to get to level 21. Your blackagumon (the one you started with) max growth level will only be 20!!!! So you have to Digiconvert a blackagmon from the wild, and keep digiconverting them until you get one that's max level is 21 or more. Then you can give it the amount of dark skill needed (it needs to have 1000 dark skill points) and the attack needed(it has to have itleast 100 atack). So there. Bye!