Removable obstacle

A removable obstacle includes any wall or acting wall which can be removed from its current square, temporarily or permanently.

In Chip's Challenge 1, most removable obstacles are Chip-removable only; the Chip-removable obstacles are the computer chip, socket, lock, boot, dirt and blue wall.

Monster and block-removable obstacles

Additionally, a bomb may be removed by a monster or block, and water may be removed by a block. In Chip's Challenge 2, slime can also be removed by a block or an ice block.

Remote-removable obstacles

The toggle wall can also qualify under this definition, as touching a green button will remove the wall, but only temporarily until another button is hit. This is the only true "wall" which can be removed from the game; a removable blue wall is half acting dirt and half acting wall.

A movable obstacle

A block counts as a removable obstacle, since it can be moved from its square and is a monster-acting wall, and also is used in many actual play situations as an obstacle to other blocks sliding.

What they do in play

Most often, removable obstacles play a part in blocks sliding in chains, such as Madness II. When a sliding object runs into a removable acting wall, its reaction and the range of options afterwards depend on the medium of sliding. It cannot slide through a teleport, as the teleport would have been skipped; if an ice stretch is used, it will continue the other direction. The most important (often the only important) situation is when a force floor stretch leads to a removable acting wall.

If a monster was sliding, it will become trapped for good on this space unless the obstacle is a toggle wall, since any attempt to remove the obstacle will cause Chip to be killed. A block will therefore become unusable. When a block slides to a stop, it is still on the sliplist and will destroy Chip if he removes the obstacle, again unless a toggle wall was in front of the block. To allow the obstacle to be removed safely, a ram would be necessary. This will be officially learned in After the Rainstorm.

Chip's Challenge 2

In Chip's Challenge 2, nearly all tiles can be removed permanently through the use of time bombs. The only obstacles left unharmed by time bombs are sockets and steel walls, and sockets can be removed after collecting the required number of computer chips. As a consequence, the only non-removable obstacle in CC2 is the steel wall.