Description: This Sentry build offers great DPS with versatility and survability.
Primary Weapon: The MDR is the best primary you can run. It hits hard, shoots fast to apply them marks and has great magazine capacity. This build has the ability to unlock all the great PvE talents. I run Destructive and Determined but you can run any other combinations.
Secondary Weapon: The SVD offers great handling and damage for quick marks. You could run any other MMR as secondary depending on preference.
Alternative Weapons: I recommend giving the Devil & Heel weapon set a try. It does great damage and it's fun to use. If you run them, roll ammo on your backpack since you will be carrying only one weapon type. Use the same attachments as the SVD but replace the underbarrel for a PEQ15- Laser or Small Laser Pointer so their reticle bloom is more manageable.
Pistol: With Toxic and Coolheaded you can switch to your pistol in a hurry and keep marking NPCs for your team. Toxic helps with crows control and Coolheaded will help you get your skills back.
Skills: You can run any skills you want. Overdose is the best to heal yourself and Flashbang allows you to apply status effects to NPCs to proc the Distracted talent on the MDR. Since Tactical Link will make it harder to remain accurate, you can run Survivor or Recovery Link instead.
Character Talents: One is None is a must to conserve ammo and do more damage per magazine. Critical Save helps you resist a bit of damage if you use a medkit in a hairy situation. On the Move goes well with the MDR play style. Combat Medic is a must in group play, everyone should use it.
Character Talents for Solo: One is None, Critical Save, On the Move, Precision.