Prison of Elders - Titan
The Titan Striker with the Fist of Havoc super has been a solid go to for PvP and damn near works miracles at close quarters when dealing with swarms of enemies. Unfortunately it's not ideal for The Prison of Elders, where you're better off fighting at a distance and don't want to put yourself in a vulnerable position in the midst of an onslaught of bloodthirsty aliens.
The best set up is the Titan Defender with the Ward of Dawn super. The bubble shield is great for emergencies, like reviving members of your fireteam who were a bit too eager to get into the fray, but you can also buff the hell out of it.
To get the jump on your foes, equip the Helm of Saint-14 to benefit from the Starless Night upgrade, that blinds enemies who enter your bubble.
You can choose from three modifiers for Ward of Dawn that will buff you and your teammates. Armour of Light will grant you resistance to damage, Blessing of Light will bestow a temporary shield when you pass through the Ward of Dawn, and Weapons of Light will boost weapon damage.
The Disintegrate melee ability generates a damage absorbing Force Barrier around your Titan, and you can build on this by equipping the No Backup Plans gauntlets and unlocking the Improved Disintegrate upgrade, that will keep your Force Barrier in play for an extra 5 seconds
You can stack this with the Relentless ability modifier that will give you a boost of an additional 5 seconds and bump up the strength of your barrier as well.