i am not sure - but are you talking about the Riddle of Sound, Smoke and Light?
If you are, then all the things needed to complete the riddles are located in the ruines, present - and not past.
What you need to do in the past, is to make sure the Guardian Golems get a fault built into them so you can destroy them in present. And also - remember to get the three planted for the Wild Mage in the garden.
If this isn't what you mean, please post again, and I'll see if I (or others) can help you better.
By the way - I've added a spoiler tag to your thread title, to avoid people getting spoiled by accident.