I still haven't found the runes that slow down time and give a bigger window to parry. Are they late game?
The only talisman that gives me an increased parry window so far is a blue one.
I'm not sure where I found it though. I definately got it before the story more or less forced me to go to the second (non-midgard) realm. So I probably found it somewhere around the lake or in other accessible places in midgard at that point in the game. It's called 'golden talisman of protection'.
Edit: whoops you were talking about runes... Move along now!