every 1 tick:
    loop all players:
        if {ika.%loop-player%} is true:
            set {_block} to location of block 1 meter infront of loop-player
            add 0.5 to y-coord of {_block}
            if block at {_block} is ladder:
                set velocity of loop-player to vector(0, 0.5, 0)