Add variables for:

Direction bomb was hit

Gravity

In the process function

Rotate the bomb as it moves

In the physics process function

If the bomb is not on the floor

Add gravity to make it fall

Call move and slide to activate physics

In the area entered function

Check if the area is in the slash group

Search the tree for the HUD_group

Call the play_flashbang function

Search the tree for the main_game group

Call the reduce_score function

Destroy the bomb