Laider

The potion, restore vital essence, gives you a temporary boost to max health and endurance. If the combat ends before the duration of the potion, the boost remains, but because your max health is reset you are in effect healed. A good reason to make this a mastered spell IMO. A bit cheap, but the need to rest is more of an inconvenience, than a realistic game balance mechanic.

Going through POTD right now and my rogue has coped really well. Don't worry about deflection, damage reduction is your friend. Sanguine plate, shod in faith, a blunting belt and tidefall are all relatively easy to obtain, think I had them by level 7. Just remember the rogue works best by being on the edge of a melee, or in one on one duels. They will destroy poorly armoured opponents. At level 10 and until I could duplicate bittercut, I used the spear that you can create to proc stun and do extra damage against immobile opponents and combined this with the shield that procs on a critical bash. A little bit of micro with debuffs/buffs and this combo would regularly do close to 300 damage with a finishing blow. I think I duplicated bittercut at level 12 and whilst this is a well known and overused set up the consistent, heavy damage means the rogue is a tank because she kills so quickly.