First off you should navigate to your Dungeon Defenders 2 config folder, this can be found normally in: C:\Program Files (x86)\Steam\steamapps\common\Dungeon Defenders 2\DunDef2\Engine\Config unless you've installed steam to another drive.


Once you've located the config folder you need to open 'BaseEngine.ini' with notepad, notepad++ etc, whichever is at your disposal. Then you'll want to hit Ctrl+F to bring up the search window in which you search for a few config lines:

bSmoothFrameRate=TRUE > Set this to FALSE - Disables the FPS cap.
MotionBlur=True > Set this to False - Disables motionblur which has a slight impact on performance, even thou there's hardly any of it in-game.
DepthOfField=True > Set this to False - Less Blur in distance and on trees
Bloom=True > Set this to False - Removes the glare effect to clouds or neon textures.
UseHighQualityBloom=True > Set this to False - Saw no difference in-game with this on, so leave it off.
MaxAnisotropy=X > Set this to 16 - Better texture filtering


---FOR NVIDIA USERS ONLY---
bDisablePhysXHardwareSupport=True > Set this to False - This will net you a slight boost in FPS depending on your GPU.
UseMinimalNVIDIADriverShaderOptimization=True > Set this to False

After these you need to hit Save and then right click on 'BaseEngine.ini' and open propeties and tick the 'Read Only' box on the bottom.

You'll want to stay in the same folder as for the engine tweaks, but this time you'll open a file called 'BaseInput.ini'.

Once it is open you'll want to look for these lines:

LookRightScale=X.XX > Set this to 0.000000
LookUpScale=X.XX > Set this to 0.000000
bEnableMouseSmoothing=True > Set this to False


---NOTE: If these bindings cause your mouse to slow down randomly in-game you're free to remove them, just keep mouse smoothing turned off.---

Under ; --- General bindings you are to add:
Bindings=(Name="MouseX",Command="Count bXAxis | Axis aMouseX Speed=2.0")
Bindings=(Name="MouseY",Command="Count bYAxis | Axis aMouseY Speed=2.0")

Bindings=(Name="LookUp",Command="Axis aLookUp Speed=+25.0 AbsoluteAxis=0")
Bindings=(Name="LookDown",Command="Axis aLookUp Speed=-25.0 AbsoluteAxis=0")

Bindings=(Name="GBA_TurnLeft",Command="Axis aBaseX Speed=-40.0 AbsoluteAxis=0")
Bindings=(Name="GBA_TurnRight",Command="Axis aBaseX Speed=+40.0 AbsoluteAxis=0")

After you're done hit save and proceed with making the file Read Only as mentioned in the earlier section.