Welcome to my first build.

 First of all I'd like to say that I'm no math expert, this is just something I enjoy so I wanted to share. I hope you enjoy this as much as I do.

I choose the skills and talents I like, tried to improve my items and this is the result.

Although it has good dps this build doesn't have best TTK times so if you are looking for best dps this build isn't for you.

Also I'm open to any suggestions.

Gearing

 

Artifacts: -- -

Alternatives: - - - -  -  -

Cybernetic Implant is just great for this build. We get 300 power which helps maintaining power and increases damage of Energy Overload. And consuming all power every 6 seconds makes the 1500 damage and 100 crit rating buff permanent in a fight.

Blessings:

Relic:

Alternatives:  for power sustain if you have problems.
                         is damage alternative.
                         is for defense (duh).

Runeword: Power Doop
You can use a bunch of placeholders for Power Doop if you don't have it but there is no real alternative for this build. High critical damage and power gain make it perfect for this build.

Medallion:
Damage rating, crit rating, health, +1 energy and spirit gain. It may not be best for TTK but it's all around good medallion for Ultron.

Legendary:
Alternatives: - -
is better for power sustain for obvious reasons but gives more damage.

Ring:   Cosmic Ring (Offensive), BDR and +3 stat. Didn't test other affixes so I don't know if this one is the bis. I'll update if I get something better. This seems like the best option though.

Alternatives: Sling Ring of the Kamar-Taj (Ranged or Energy)

If you don't have those an ICP ring ( - ) is a good alternative.

Uniques:
Slot 1 - ( - )
Slot 2 - ()
Slot 3 - ()
Slot 4 - ()
Slot 5 - ()

Fragment seems equal to Rifle but I'm not sure. His own unique is probably the worst out of this 3. If you don't have Rifle I suggest you farm Crossbones in any patrol zone because it is very easy to obtain one right now.
For his slot 4 I don't have an idea to be honest. I'm using Skrull Uniform until I come up with something.

Enchants:
A.R.M.O.R. Damage upgrade for slot 1-5
A.R.M.O.R. Health Upgrade for slot 2-3-4

Challange Bonus: Durability>Energy if you have enough spirit regen

Insignia: Mockingbird might be a good alternative but I think we have enough attack speed.

Team-Up:

I like using Ultron alone so I use my team-up as away.

Powers and Talents

All talents are energy based.
Improved Survivability for power sustain.
Focused Microwaves for making Operation; Irradiate a range ability.
Pulsing Wrath for power sustain. It's the key for this build.

Skills:
- Overcharged Blasts
- Operation: Dash
- Energy Overload
- Encephalo Beam
- Operation: Swarm
- We Are Ultron
- Operation: Annihilate
- Operation: Irradiate

Alternatives:

- Operation Crush instead of - Operation: Swarm for Power Doop proc.

Power Bar:


Rotation is very simple, keep everything on cooldown. Only thing you need to keep in mind is using Operation Irradiate after Energy Overload and when power restores to half. You can use medkit to boost it a little. This will help you max your power for 2 Energy Overloads.

Energy Overload - Operation Irradiate (when half of power restored) - energy Overload - Medkit (Pulsing wrath effect continues) - Energy Overload
Spam other skills in between.

Hero Synergy:
Cable
Captain Marvel
Cyclops
Gambit
Hawkeye
Iron Man
Squirrel Girl
Star-Lord
Thor
Vision