- During "Robot Transmission Mode":
- Up, Down, Left, and Right move the arms.
- A opens the arms, and B closes the arms.
- While controlling either Professor:
- Left and Right moves them horizontally.
- Up and Down are used to climb ropes.
- The A button picks up or drops a turnip.
- Start switches to "Robot Transmission Mode"
- Select pauses the game, and pressing Left or Right while paused will scroll the screen
You play as Professor Hector, a somewhat aged scientist, as he must traverse his expansive laboratory in order to collect and defuse the dynamite which is scattered across his lab. You have a set about eight minutes to use R.O.B. to move "Gyros" around in the real world so that either the A or the B button on the second controller will be pressed, causing the blue and red pillars in the game to move up or down. You cannot jump, but you can climb vines, use moving pillars to go up or down, or fall off of platforms to move through the level. You also must avoid the many Smicks which wander around the stage, which will bite the player when touched. Smicks can be distracted using turnips, which can be found and picked up in some levels. While distracted, the Smicks stop moving and can no longer harm you temporarily. Pressing select will allow you to direct R.O.B., but you will have to stop moving, which can possibly leave the player in a vulnerable state.
There is also a two-player mode, where the players will switch controllers periodically, with player two controlling Professor Vector during their turn. Alongside the two player mode, there is also an endless Game B mode where you must control R.O.B. to move pillars so that the sleepwalking Professor Hector doesn't get stuck or hurt.
Two more functional options include the "Test" and "Direct" modes, each serving as a way to set up and test the R.O.B. and ensure that it can properly interact with the game, using the green screen flashes. During the Test mode, a green flashing box is displayed in the middle of the TV screen, which sends a signal to the R.O.B. to light up the small red light on its head, ensuring that the connection works. Direct mode allows you to directly control R.O.B. using the controller, using the D-Pad to move its arms and A and B to open and close its arms.
In order to play the game correctly, you need to have the following items:
- A CRT-Type television (Other types will not work with the R.O.B.)
- Two Gyros
- One Gyro Holder
- One Gyro Spinner
- One Controller Tray
- This game is one of the only two games that had support for the R.O.B., with the other game being Stack-Up. Unlike Stack-Up, this game is fairly common because it was included as a pack-in title with the NES Deluxe Set.
- This game is the only appearance of the "Smick" enemy, and the last appearance of Professors Hector and Vector.
- Some copies of the game have a hidden Famicom to NES adapter inside of them, which is present only because Nintendo was rushing to release the game on time, and chose to simply put the Famicom version of the game inside an NES shell. Other games that have this adapter include Clu Clu Land, Excitebike, and even Stack-Up.