I solo'd the abyss with my hunter at 31 using Bladedancer all legit. Equip Patience and time, make sure your skill tree is set for escape artist, stalker, shadow jack, and vanish. You have to skip the second lamp, go invisible at the start, run to the first lamp and then cut through to the third lamp by hitting the first thrall you see to go invisible. The rest of it is just toggling your invisibility skills to stay hidden and keep the thrall horde off of you. Once at the bridge you explode the lamp, activate the bridge and jump on the left rock - and this is where it gets tricky: Switch from shadow jack to fleet footed and crouch - your invisibility from crouching will last about ten seconds, after about five seconds in that time frame you ADS of your P&T and hold it. If done right there will only be a fraction of a second in between losing your invisibility from crouching a gaining it back from P&T. Keep ADS until you switch from being invisible from P&T to being invisible from crouching. Once that happens to stop ADS and wait another five seconds and do it again - just rinse and repeat that until the bridge is built and the ogre will never see you. Once you're ready to cross - make sure you're invisible from crouching and book it across the bridge. Congrats you just solo'd the abyss on hard mode and you did it legit ;-).