How do i get battlespire into full screen , Right now its just a small screen with a very large black boarder please help :*(

It's hard to help you since you provided no information about your system (hardware, OS, etc.).

However you are probably experiencing a resolution issue: your graphic card is probably configured to fill fullscreen with black borders.
Since the game's default resolution is 640x480, I think you should try one of these possible solutions:
- Force DOSBox to upscale the game's resolution in fullscreen mode (you have to edit the game's conf file).
- Changie your graphic card settings in order to scale the game's resolution to your desktop resolution (look for the appropriate settings in your graphic card management tool).

I have Nvidia and i have it all set to full sreen i cant find a thing that says anything about black borders. No matter what i try it wont get to a fullscreen

This is what it looks like

Open the nVidia Control Panel, select "Display", then "Adjust desktop size and position": which is the selected scaling mode?

Fullscreen and resolution 1920x1080

This is the correct mode to upscale the game: are you sure that the PC actually uses the nVidia card when the game is running? Is your PC a laptop, tablet or some other device with a particular display?

Its a deskstop , and im pretty sure its using the nvidia card . Is there a way to check that ?

Well, if your PC is a desktop computer, you can check which card is using by simply checking which port your monitor cable is connected to! :-)
Laptop computers may have two GPU: one integrated into the CPU and one separated. They use the former or the latter mainly depending on power saving settings.

Well, I'm running out of ideas: as far as I know the graphic driver should upscale the game to your fullscreen resolution. Maybe there is a problem with your monitor settings.

Go into your installation folder: there should be a file named "dosbox_battlespire.conf" or something like that. Can you post it here?

it wont let me post it its the wrong format , its not the end of the world i can play it on a small screen. i just wish i could change it XD

I meant you could copy and paste it here, as it's a text file.

It wont let me i dont think , it just kept processing the post and never post
[sdl]
# fullscreen: Start dosbox directly in fullscreen. (Press ALT-Enter to go back)
# fulldouble: Use double buffering in fullscreen. It can reduce screen flickering, but it can also result in a slow DOSBox.
# fullresolution: What resolution to use for fullscreen: original, desktop or fixed size (e.g. 1024x768).
# Using your monitor's native resolution (desktop) with aspect=true might give the best results.
# If you end up with small window on a large screen, try an output different from surface.
# On Windows 10 with display scaling (Scale and layout) set to a value above 100%, it is recommended
# to use a lower full/windowresolution, in order to avoid window size problems.
# windowresolution: Scale the window to this size IF the output device supports hardware scaling.
# (output=surface does not!)
# output: What video system to use for output.
# Possible values: surface, overlay, opengl, openglnb, ddraw.
# autolock: Mouse will automatically lock, if you click on the screen. (Press CTRL-F10 to unlock)
# sensitivity: Mouse sensitivity.
# waitonerror: Wait before closing the console if dosbox has an error.
# priority: Priority levels for dosbox. Second entry behind the comma is for when dosbox is not focused/minimized.
# pause is only valid for the second entry.
# Possible values: lowest, lower, normal, higher, highest, pause.
# mapperfile: File used to load/save the key/event mappings from. Resetmapper only works with the defaul value.
# usescancodes: Avoid usage of symkeys, might not work on all operating systems.

fullscreen=true
fulldouble=false
fullresolution=desktop
windowresolution=1920x1200
output=Overlay
autolock=true
sensitivity=100
waitonerror=true
priority=higher,normal
mapperfile=mapper-0.74-2.map
usescancodes=true

( it let me post this , and by reading it maybe this is what im looking for ?

I'm not sure, because these settings seem correct to me, but I would like to read the whole file.

Anyway, I have a last suggestion, after which I'm afraid I'm not able to help you: run the Graphic Mode Setup tool and try to switch to another Graphic Mode, such as DDraw or OpenGL.

OMG THANK YOU ! THE DDRAW WORKED ! I LOVE YOU !

I'm glad to have helped you.

It is normal that the GPU won't upscale the resolution, since DOSBox output is yet matching your desktop resolution but the problem was in DOSBox itself because it wasn't able to upscale the game to fullscreen and it simply filled the screen with black borders. As far as I know DOSBox should upscale resolution even in Overlay mode, but evidently I was wrong and the DDraw mode is needed instead.

Another solution could be running the game in the original (640x480) resolution and then let the GPU to upscale it, but you don't need to try it since everything works fine now. Good playing.