As you have probably already realized the Bionic Commando Rearmed Controls aren’t the easiest to get used to. I would highly recommend playing this game with a steam controller. If you are playing on your keyboard I would switch up your controls to make the game more enjoyable.
These are the default Bionic Commando Rearmed controls. Instead of using WASD to move around you will be using the arrow keys. To fire your weapon and use grenades you will use k and l. In order to change the weapons you will use the two next keys up which are i and o. To use your bionic arms grappling hook you will press the j key. Then wind yourself to the target press the j key again. To disconnect the grapple you will either press up to climb onto platform or press down to drop back to the ground. Also to access your inventory you will press u and pause with 1.
Now let us try and improve upon these controls a little bit and make the game a bit easier to play. First off lets go back to using WASD to move around with because that feels right. I then used the q and e keys to control my inventory and pause keys. I personally love using my mouse so I couldn’t help but putting my weapons all on it. My left click is used to shoot my gun and my right click is used to grapple. The mouse wheel click is used to throw grenades and the forward and backward mouse buttons are used to swap guns.
If your mouse doesn’t have extra buttons on the sides I would add your weapon swap to mouse wheel up and mouse wheel down. I have found that I will accidentally throw grenades when trying to switch weapons if I have that setup however.
I personally enjoyed the game much more with the new controls. You may want to tweak them a bit more by moving around the grenade or inverting the grappling hook and fire keys. I hope you enjoy your new setup and best of luck.