Framerate drop on the clock tower level

There are four anticubes in the clock puzzle. Each will show when one of the clock's four hands hit the top. There is a limited window for catching the anticube before it disappears. The times differ between consoles, but the hands' speeds are the same:

• Red cycles every minute.
• Blue cycles hourly.
• Green cycles daily (24 hours).
• Gray cycles every week (7 days).

You'll need to check your clock and figure when it'll hit the top. Either check back then or change your 360's time from the system settings (you'll need to disconnect from the Internet).

E.g., my blue always hit at :15 past the hour, my green always hit at 7 p.m. (once a day), and my gray hit at 4 a.m. with a rather large window (since it moves slowly).

You need to lower the water. The sound you hear is a door submerged underwater.

Where does the door lead?

It's a 64-cube door. It reveals a room with a floating heart. It fills with three red cube pieces. This room is considered an Easter egg.