Follow the instructions for
to start the old Maniac Mansion.
You first need to select some characters. Some characters have a much too good conscience to kill the hamster, so not all characters work for this.
I chose Bernard and Syd.
After the game started, take Syd and go to the front door of the mansion.
Pull the door mat to reveal the front door key and unlock the front door with it.
Enter the mansion, and before you enter the first door next to the clock, read the next sentence, as you need to be prepared to run away in the opposite direction!
CAREFULLY walk through the kitchen, and let the scrolling screen catch up (do NOT click past the kitchen sink), because as soon as you can see nurse Edna standing in front of the fridge, run in the opposite direction out of the kitchen.
Enter the kitchen again, go all the way through and enter the next room. Go past the large dining table and into the next room. On the shelf you will find some fruit juices. Pick them up.
Return through the dining room and the kitchen and go upstairs.
Before going through the security door, head left and go into the painting room. Pick up the bowl of wax fruits. Go back to the security door and go through it.
Now be careful. Eventually a cut scene shows Weird Ed Edison getting hungry and leaving his room. Find the nearest safe room to enter and wait until you see him reach the kitchen.
Otherwise he'll meet you on the way down to the kitchen and lock you up in the dungeon.
After the security door, go right and up the stairs. You will meet Green Tentacle. Give it the wax fruits, then the fruit juice and it'll let you pass.
Go upstairs again, and go into the fourth door into the room with the sarcophagus and the training machine.
Switch to a "New kid" and let that kid go to the front door.
On the left door is a door bell. Ring that door bell, and Weird Ed will go down to check the door.
After you've seen him leave his room, wait for about five seconds, go out the training room and into the next room on the left into Ed's room.
Pick up his hamster and return to the training room.
Wait for the cut scene where Ed reaches the front door and scolds the kid outside, and then wait again about 30 seconds to make sure Ed has returned to his room.
With Syd and the hamster, go down to the kitchen, open the microwave oven, use the hamster in the microwave oven and close the microwave.
Turn the microwave on and wait a few seconds for the achievement to pop.