The Disruptor: A Keeper Co-op Build

Playing Keeper requires skill and thought. She doesn't have perma-barrier like Arcane Warrior and has modest DPS. However, she does have two unique skills (Static Cage and Disruption Field) that allow you to control the battlefield and have fun while doing it.
The build is best when used as part of co-op team...that actually cooperates

Skills:
Decloaking Blast (Fade Cloak upgrade) -- primary DPS ability
Lightning Cage (Static Cage upgrade) -- secondary DSP ability that paralyzes enemies and applies lightning damage. Be sure to hit enemies with staff attacks to trigger Lightning Cage's effects
Stasis Lock (Disruption Field upgrade) -- One of the coolest abilities in the game. Enemies are nearly stasis, which allows for complete and total control of the battlefield
Elegant Defense (Barrier upgrade) -- Cast as often as possible to leverage Mana Surge to freeze enemies and setup combos or to use Decloak

And most of all, remember that there is no 'I' in 'Team' so play cooperatively. Some great team compositions can consist of:

1. Avvar with Crushing Leap. Shatter frozen enemies or detonate enemies paralyzed by Lightning Cage to generate combos
2. Katari with Might Blow and the Dancer's Axe. Shatter frozen enemies or detonate enemies paralyzed by Lightning Cage to generate combos. Dancer's Axe Whirlwind attacks are super fun when a group of enemies are trapped in Stasis Lock
3. Necromancer with Walking Bomb and Winter's Grasp. Insert Walking Bomb inside the lowest HP enemy and watch the explosions inside Stasis Lock. Freeze and kill an enemy with Winter's Grasp while paralyzed in Lightning Cage to freeze all nearby enemies. If well-timed, a large group of enemies can be frozen above ground in Lightning Cage (requires Necro's Virulence passive)
4. Archer with Long Shot. Shatter frozen enemies or detonate enemies paralyzed by Lightning Cage to generate combos. Leave Spike Trap on the bench
5. Legionnaire with Counterstrike and Shield Bash: Taunt with Counterstrike to draw in enemies. Use Shield Bash to shatter frozen enemies or detonate enemies paralyzed by Lightning Cage to generate combos.
6. Elementalist with Stonefist and Fire mine. Use Stonefist to shatter frozen enemies or detonate enemies paralyzed by Lightning Cage to generate combos. Use Fire Mine in Stasis Lock to incinerate enemies in slow motion. So fun
7. Alchemist with Flask of Frost, Twin Fangs and Shadow Strike: Use Twin Fangs and Shadow Strike to shatter frozen enemies or detonate enemies paralyzed by Lightning Cage to generate combos. Use Flask of Frost to freeze enemies inside of Stasis Lock. Don't use elemental mines near Stasis Lock. There is a long-standing bug that causes the mines to fly well above Stasis Lock and not hit enemies