Hi, this is a guide on how to play 2-player BOR on 1 PSP (Sorry if everyone knows how to do this already but I have never heard anyone mention it)
STEP BY STEP INSTRUCTIONS
Ok here we go:
1. Install BOR on your PSP and start up.
2. choose your bor.pak (I will be using the original game by the senile team)
3. When the game has loaded press start and navigate to the control options main menu > Options > Control Options
4. Select: Setup player 1 and make sure move up, down, etc are there corrosponding arrows (move up - up arrow)
5. You wont have sufficant amout of keys to use: special + jump so when you get to these options have one as hold (press down hold after selecting) and one as home (same instructions as hold)
6. Make sure that attack is L trigger and start is well..start and select OK (remeber using L Trigger which is your new attack/selection button)
7. Do the same for Player 2 except for these keys:
move up: /\
Move down: X
Move left: 
Move right: O
Special: No key (Hold)
Attack: R Trigger
Start: Start (This may not work)
And press OK with the R Trigger
8. Navigate back to the main menu and select: Start game, then choose your difficulty.
9. Here we go, this is were all the key fiddling pays off: Player 1 choose your player with the left/right keys and select with the L trigger. Player 2 choose your player with the square/circle keys and using R trigger to select and Begin!
10. Now you are in the game get used to the controls, the only attack avalible is normal attack so its extra hard!
Control Problems: Sometimes the controls will freak out, eg, The player may start using special instead of attack and jump instead of walk, you'll just have to deal with it (This only applies for player 1)
Normal Controls: If you want normal controls back you can change them in the main menu or just delete the settings.sav in the BOR folder.
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