The Iris Brooch with no knockouts, kills, detections and only special arrows.

[tigerpoetry]

So I got 'Something to prove'. Amongst others, the stuff in the title added to my 725 difficulty points on 'Master'.

I'd not taken the Amber Circle or Iris Brooch and hadn't got around to the Golden Keep, as it was pointless without the others. The Iris Brooch was too much trouble when doing that Basso job. I decided to see if I could get it, then go for the Amber Circle... whoa! Tough. This was my method. It took ages. I'd like to know if it could've been obtained easier.

1: Enter the hideout, snuff the candle nearest the window and duck back out again.
2: use a distraction to douse the candles on the table in the next room without Jebs noticing (tricky). Duck out again.
3: use a water arrow on Jeb's torch... he never re-lights it. Dive back out of first window.
4: Hide near the doorway to the second room and sneak around, open the wardrobe and smash the vase. Exit by the second window again.
5: re-enter hide and swoop to wardrobe to snuff the candle inside it. Exit by 2nd window again.
6: re-enter the hideout, push the button in the wardrobe and exit by the second window a third time.
7: re-enter, hide in doorway swoop to fireplace and pick up the Iris Brooch, turn and swoop to the window to kick Garret out of admiring the collectible.
8: exit to South Quarter!

It may be possible to cut out some of the steps around the wardrobe, but I got detected so often, I decided to play it safe.

Phew! I got it but it took as long as some small side quests.