The Elder Scrolls IV: Oblivion Guide - Knights of the Nine
4: Nature's Fury
With 'Nature's Fury' set as your active quest, an arrow will point to a location west of the Imperial City. Fast travel to the location on your map closest to this point, and then follow the arrow on your compass the rest of the way. When you reach the spot, you will find yourself stand before a giant statue.
At the statue, locate and speak to Avita Vesnia, who should close by, Select the 'Boots of the Crusader' dialogue option, and then agree to take the test when the option comes up. The arrow on your compass will now point to the Grove of Trials. Make your way to the Grove of Trials and stand in the middle of the area; you'll know you're standing on the right spot because an in-game 'Quest Updated' pop up will appear.
Do not attack the Forest Guardian when it appears in the Grove of Trials to pass Kynareth's test.
Once you're standing on the correct spot in the Grove of Trials, remain where you are. The Forest Guardian, which is a giant bear, will appear and attack you. Don't fight back; let the bear hit you a few times, and an in-game pop up will soon appear, informing you that you passed the trail. A boulder will then fall nearby, revealing a door into Kynareth's Grotto. Enter Kynareth's Grotto to spot the Boots of the Crusader on the pedestal straight ahead. You won't meet any resistance from the Spriggans in the grotto, so just grab the boots and get out.
Passing Kynareth's test in the Grove of Trials.