File:Behind the Stained Glass

I guess the fact I drowned inside of the stained glass at the Sunken Castle meant something after all. What does it mean by another castle though? What other castle is there? (Model by SigmaShield after I failed to make it myself, and the filter was added by Pietro_Ultra like the other tapes.)
 * 1) SuperMario64 #EveryCopyOfSuperMario64IsPersonalized #SM64