This terrifying abomination can be found lusting for blood somewhere in the catacombs. Once he sees you he will agro and wiggle out a few tentacles to help him move around the level. He will spawn two gore balls until you get him to about half heath then he gains a third one, and ever later in the fight he will get a fourth. He will spin these balls around and throw them, they are his only way of causing damage but they do deal a lot of it.
For the abomination it is best to use melee to take him out. Slip past the gore balls and spam attacks on his body, and slip away before he starts to throws them.
For range you’ll have to be careful because this boss has a lot of mobility. Use as much of the level as you can to safely run and line up shots.
Magic is pretty hard to use you will need some strong spells. Frost nova combos well with melee, but if you’re more magic on a run, then use your strongest long range magic.
The necromancer can be found pondering life and death somewhere in the catacombs. Once you agro him from getting too close, he will start to summon a lot of skeletons. If these skeletons get too far away from him they will break into an explosion of bones. Killing the skeletons can also cause them to blow up. The Necromancer can turn the dead bones into a small homing bone storm that will chase you. If you are too far out of range of his skeletons the necromancer will come to you flying threw even the walls and floors. He will float away if you are in his face attacking a lot.
Melee is great if you can take out his little skeletons, because he himself doesn’t have any attacks. Get in his face and watch your back.
Range is the hardest for this boss because his friends will get in the way, your best shot is to get him to float away from them to get a hit in.
If you want to use magic against him you’ll want to use magic that will go through his skeletons and git him like shockwave and chain lightning.
The zombie dragon will be found sleeping in the catacombs he will agro if you are too close or attack him. He has a similar move set to the caves dragon but a lot more complex. He has four attacks, a dash that if he slams into an object he will shake the level and if you are touching the ground it will deal damage. There are three variations to his fire balls: a burst of 7 shots; a blast of 7 shots all at once that don’t fly straight; and a charged fire ball that flies very fast and deals a lot of damage.
For melee play like you did against the cave dragon, just be careful. Draw him in and deal damage then run and hide.
When using range against him try to use as much of the level as you can so you can line up shots when he comes for you.
Magic can be scary against him because of his variety of attacks and his getting closer. Use fast charging magic or longer range magic.