1. Loki

2. Venom

3. Ultron

4. Thanos

5. Baron zemo

6. Red skull

7. Maliketh

8.Abomination

9. Ulysses claw

10. Ronan

Venom isn't in the MCU.

I think more this:

1. Loki

2. Ultron

3. Ronan

Uh whiplash duuuuuuuuuh

1. Kingpin

2. Kilgrave

3. Loki

4. Hive

5. Ronan

6. Ultron

7. Cottonmouth

8. John Garrett (he had some of the best lines!)

9. Red Skull

10. Aldrich Killian

yo I wouldn't consider Loki being a villain now

10.) Red Skull (Captain America: The First Avenger)

9.) Hive/ Grant Ward ( AoS...I know they're two different people but I'm counting them as one.)

8.) Johann Fennoff (Agent Carter season 1)

7.) Madame Gao and the Hand (Daredevil/ Iron Fist)

6.) Crossbones (Captain America films)

5.) Ultron ( Avengers: Age of Ultron)

4.) Loki (Avengers​/ Thor films)

3.) Kilgrave (Jessica Jones)

2.) Zemo (Captain America: Civil War...just because his plan to tear apart the Avengers actually worked...without him having to die.)

1.) Kingpin (Daredevil season 1 and 2)