if you ' re trying to do a solo with a character that doesn ' t have anything to restore shields or increase dmg reduction , you either are a masochist or have a shit ton of spare time and patience . Not really , crowd control staggerstun and high DPS gives you alot more survivability than restore shields or dmg reduction , simply because the enemy can overwhelm you regardless how often you restore shields . The Volus character is a perfect example , its possible to do a build focused on spamming Shield Boost power to grant you a constant shield regen , that strategy however as a negative impact on DPS and use of powers that could be used for crowd control . What happens is that you take too much time to kill enemys , at later waves you get so overwhelmed by enemy attacks that shield regen and DR can ' t save you .