Robot Unlock is a puzzle game by Madflame Software in which you're challenged to program a robot to perform certain tasks. What sort of tasks, you ask? Is it vacuuming the carpet starting along the outside walls and working in toward the center? Is it making breakfast sandwiches and wrapping them in foil for you and your co-workers to nosh on during the day? Is it riding a unicycle through a world of perilous flashing neon blocks? Nope, it's a much simpler, more worthy task. MATHS. Write that down in your copy book now.
In each level of Robot Unlock, your goal is to program a path for your Executor robot to travel around a series of command tiles that alter the robot's stored memory. Your memory consists of four slots, each of which hold a number. In some levels your starting digits are randomly generated, while in others the numbers are constants, but your goal always remains the same; change the input (Initial Code) in your memory to match the output (Required Code) on the right. As instructed by Ted, your friendly robot guide, the Required Code has to match a certain set of criteria based on the Initial Code, such as swapping the numbers in the first two memory slots or comparing the input values and moving the third-largest to slot 1.
Your instruments through this journey are a range of mathematical stepping stones which can be placed along the Executor's path, as well as two indicators to mark your position in the memory, colored dark green and light green. You can move the memory pointers left and right using the double-arrow tiles, then perform mathematical equations that compare the numbers held by the pointers, with the output replacing the number in one of your slots. It would take a long time to discuss every possible operation, but know that you can perform the four basic operation (add, subtract, multiply, divide), force the robot to take a detour if one number is greater than another, and other functions.
Once you think you know how to program your speedy robot, use the toolbars at the top to select the tiles to drop down below. You have three palettes to choose from, including one that features commands relating to the dark green memory pointer, one for the light green pointer, and a blue tileset that corresponds to the movements of the Executor itself. Click on a tile to use, then click on the grid to plop it down there. When everything's in place, hit the play button and watch as your robot works it's magical mathematical mojo. Your bot will follow the tiles you've set until it falls into "the abyss" surrounding the play area. If your memory matches the required output, you'll unlock a new level for fiddling about in.
Analysis: Robot Unlock taps into a very basic concept employed by what is essentially its chemistry-based predecessor, SpaceChem. Each level challenges you to solve a complicated problem using only the resources and space provided. As I was playing through this game, I found myself frequently longing for a way to change higher numbers into 1s and 0s quickly, without repeatedly ticking down one digit at a time until the target is reached. There's not a false sense of difficulty that comes from the lack of available tools, but a pleasurable challenge of simplicity that hits you in the forehead when you realize how quick and easy the task is (for example, dividing a number by itself gives you a 1, subtracting a number from itself gives you 0).
That said, finding those solutions can still be a tricky mess. Determining the plan of action is often times the hardest part of each puzzle, given how few resources you have to work with. One factor that greatly contributes to the difficulty is the randomness of the input numbers given. Very much unlike SpaceChem, where the inputs are constants (or are limited to three possibilities), any integer (with a limit of +/-100ish) is fair game. You can't just program a path that works for one set of numbers that you think might pop up, you've got to program a path that works for every set of numbers.
Along this same vein, there's a pseudo-bug worth mentioning. Since the numbers are randomly generated, it's entirely possible that a set of numbers will satisfy the output conditions, without a single tile laid down. In the early levels, this is overlooked and treated as a valid solution. As far as introducing people to concepts goes, this isn't the greatest way to start off the game, since you can bypass levels in which you familiarize yourself with critical strategies. However, this is corrected in later levels with the requirement that your program must function three consecutive times in order to pass. It's a good save, but it really would be worth considering for use earlier in the game.
Unfortunately, this game's interface is a bit crude, which can lead to some confusion if you're not careful. One problem is that while selecting tiles, there's no way to tell what tile in the palette you've selected, such as highlighting your choice or a separate indicator. Also, Ted's instructions, though helpful, can linger on the screen a bit too long with no way of working around them or clearing them without waiting a short period of time. They're minor presentation quibbles, but they can become grating after a while.
Still, Robot Unlock packs some difficult challenges into a fun atmosphere. Just like other programming games, you might spend more time working outside of the game to produce an answer, but seeing your analysis pay off in the end (with, well, pixely fireworks) is worth it, just to know you trounced the troublesome task. If you're looking for a number-crunching challenge that emphasizes how you crunch rather than the numbers themselves, Robot Unlock is here to satisfy your need. And who knows, maybe it does help with the vacuuming.
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