Gameplay
Each level starts with Roger climbing up a ladder set into the floor, and the player completes the level by arriving back at this ladder with Rover - at which point Roger climbs down with Rover.
Gameplay involves getting Rover out repeatedly in a set of increasingly difficult levels, by moving objects around in a grid to open up a path to get to the dog and then bring it back out.
There are four different types of robot in the game, each with different behaviour. One type shoots Roger if he stands in front of it, but doesn't move, another type runs around and shoots Roger if he is seen, another type chases Roger around, and the last type runs around and kills Roger if it runs into him. To get to Rover, the player must normally avoid, trap or destroy them.
There are various items which Roger can push around in the world: crates (which float on water), mirror blocks (which reflect lasers at an angle), star pearls and anti-grav carts. Other items in the areas are grated floors (which robots cannot travel on), glowing floors (which Roger cannot travel on), water (including moving water in which crates float with the current), laser projectors, teleporters and force doors (which need an access card in order to be opened).
Read more about this topic: Rescue Rover