that sounds boring and easy...
you need to program movment into the enemies. Random, moving towards the player, and moving away from the player are good options. Also, enemies that mirror your movment opposite are good options too.
some of the enemies that move away from you could also shoot projectiles to make them difficult. although you'll have to give the player an item that either shoots projectiles, has a long reach, or can deal with them in some way. the ones that move away from the player can also add a depth of intelegence to the game if there's pits around, or other objects that can hurt them. same with the mirror oppisite, although with that one, you'll have to find a way to discourage the player from using there sword.
statinary enemies can make the game fun, only if there done right. shooting projectiles is one option, but overdone. reversing gravity or messing with the players controls when they get into a certain radius can be an interesting option. spawning smaller enemies can also be another option for statinary enemies, they would have to destroy the spawner before they could take care of the spawn. heck, that could be an idea for a "beat all enemies" kind of room. another option could be reducing walking speed, that could be used in a room with projectiles and/or fast enemies. one last option for statinary enemies i can think of is whack-a-mole type enemies. ones that disappear underground, and pop up in another place. they have sevral options for what they could do to make things hard for the player