In Ratchet and Clank: Going Commando and Ratchet and Clank: Up Your Arsenal, the very cool and interesting Insomniac Museum is a hidden planet in the game where those talented and lucky enough can go to visit some awesome extras, cutting room floor material, minigames, effects, animations, weapons, and other features via a detailed and 3D edition replica of the Insomniac Games' offices.
 How To Get In (Ratchet & Clank 2: Going Commando/Locked And Loaded)
1. Collect all weapons, upgrade to the max and buy all mods. It should appear in the shortcuts menu.
2. Go to Planet Boldan. Start to go through the main area where you fight all the Thugs-4-Less henchmen. When you enter the room that splits in to two paths, take the one opposite to the path you need to take to complete the level. you should be in a courtyard overlooking the big clock. This clock is quite special, as it runs according to the PS2 clock. When this clock hits 3:00(3:00am in the PS2 clock), jump on the fountain that should be in front of you when facing the clock. This transporter will transport you to a different part of the level. Get out your weapon and kill the Thugs-4-Less henchmen. then activate the second teleporter at the far end of the room. this will take you to the Insomniac Museum.
3. This third way is a glitch. it will not harm your game or your PS2, although you will have to harm Ratchet!
Go to Boldan, like you would for #2, although this time, take the path that leads you to the grindboot part of the level. do the grindboot part, although just before the construction site, you need to jump off and glide to the platform on the left. you need to do this by jumping to the leftmost wire and either getting Ratchet electrocuted or running him into the transformer (the pink things you need to avoid). Once you're on there, you need to keep right, then when you can't go right anymore, take the left path. you will then see a locked building. Jump on the leftmost blocks connected to the building and run along them. You should fall through the blocks. run to the right so you are directly underneath the interior(you can tell by the texture of the floor). get your weapon out and jump up on top. Go into free aim mode for a bit and then go out of it. this brings the camera to the surface. Shoo the Thugs-4-Less henchmen and activate the teleporter at the end of the room. this will take you to the Insomniac Museum
 How To Get In (Ratchet & Clank 3: Up Your Arsenal)
1. Collect/achieve all of the game's 15 trophies. Once you have recieved all 15 trophies, the locked doorway inside the Trophy Room in the Phoenix will now allow you to enter. Just head on through and you will be teleported to the Museum.
2. The second way to enter the museum is through a special teleporter on Metropolis. The pad can be found through the window on the left right before the swing target leading to the level's fist Titanium Bolt. For tghe most part, the teleporter is not operational, but if you return it to when all good Insomniacs are awake - between 3:00am and 3:59am - it will turn on and transport you to the museum. If you do not want to wait until the wee hours of the night, you can manually adjust your PS2's internal clock.
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