This level set has 2 secrets in it.
A read-me file inside the game gives some hints to where the secrets can be found. It says the following:
Rumour has it that the two secret levels can only be reached using moving teleporters.
Another rumour says that the doorways are hiding near to glass shards.
Note where the two nails are lying back to back in the level, the ones with the glass shards on top of them. The doorway is right in the middle of these nails. To get to it, you have to be really quick when the level starts. Move the green duck to the left immediately. Bounce on the springs up to the orange duck, and move him to right onto the spring. This will blow a hole into the floor above, allowing the moving reciever to land on the nails. As soon as the orange duck has hit the spring, move the green duck down to the teleporter sender below. If done quickly enough, the reciever will still be on the nails. You will therefore be teleported onto the nails and can enter the doorway.
At the top right of the level is a small platform with a glass shard on it, just left of the time machine. The doorway is to the right of the shard, near the edge. To get there, use your bridges to free the moving reciever and porcupine from their platform, and make it move towards the green duck. Place a bridge up to the time machine so that the reiever can reach it. Note that the porcupine will have to move past the green duck, and so move the green duck into the sender just before it reaches the sender. When the reciever is at the time machine, place another bridge up to the platform containing the secret doorway. Move the green duck back into the sender to send him up to this platform to enter the sercret level.
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