On jump:
    if block at location 0.001 meter forward player is not air or water or lava:
        wait for 1 tick
        push player up at speed 0.2
        push player backwards at speed 0.8

On jump:
    if block at location 0.001 meter forward player is not air or water or lava:
        wait for 1 tick
        push player up at speed 0.2
        push player backwards at speed 0.8