need help in FF:CC.

I'm currently playing final fantasy crisis core and i'm having some problems in the stage "lake of oblivion"

i know that you should beat the monsters that come out of the lifestream when you examine it

but everytime i examine it it only says "the lifestream has ascended and crystalized".

what should i do?

i already tried to search for tips in the net but to no avail.

will accept any kind of tips.

thanks!

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