Single Player Walkthroughs
Part 3: Heinrich
Map Name: end
While certainly tough, the last level is beatable. The key to beating it is to have a lot of ammo going into the level and to not get stuck inside the building at the beginning. You should rush out of the building and head straight for Heinrich. When you are in a wide open area, you can easily avoid damage from Mariana's Magical Skulls and the Skeletal Warriors. It will also be easier to avoid Heinrich's Tortured Soul attack; this is just like Helga von Bulow's Tortured Soul attack which does massive damage and blinds you.
I would use the Tesla Gun since it deals damage to all the enemies. You should also switch to the Panzerfaust sometimes and hit Heinrich with that. After you run out of ammo for those two, use up your Flamethrower and then start using the Venom. It takes a lot of fire power, but he will eventually die.
Do not worry about the other enemies - only concentrate on Heinrich and dodge the others. They will die from the Tesla Gun's branching attacking. The Skeletal Warriors are melee units so you will be fine if you keep your distance. It may be worthwhile to kill the Zombie Priestess (Mariana Blavatsky), but you can probably get her with the Telsa Gun when attacking Heinrich.
There will always be three Skeletal Warriors since as you kill them, Heinrich stops to resurrect some to take their place. Thus, it is good to kill them with the Tesla while attacking Heinrich since it will force him to briefly stop attacking.
Stay a decent distance away from Heinrich so that he can't hit you with his sword. Also, avoid running away from Heinrich - if you aren't dealing damage to him, he will use his Tortured Soul attack. Only run if you need to get some health packs.