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Final Fantasy VII/List of things that are easy to miss
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
This module intends to have list of things that have to be done at certain parts of the game, or items that are only available at certain parts of the game and have to be picked up at that point or they'll be missed for good.
Shin-Ra Headquarters
There's two ocassions to go here. Better take them on either visit.
One of Turtle's Paradise posters.
Chocobo jockey room
Ramuh materia
Great Glacier and Gaea's Cliff
These items at the Great Glacier aren't permanently missable, though they're not available for another grab for quite a while if you miss them at the beginning of CD2.
Alexander materia
The following are permanently missable, since they reside on the Gaea's Cliff, which means they can be only got at the beginning of CD2:
Ribbon (Ribbons are extremely rare, so it pays to get this one. See Things to Collect.)
Temple of the Ancients
Most of the items, especially the Morph materia which can be found only here.
Yuffie's home
One of the Turtle's Paradise posters.