The Avengers Under Siege Event began on 7 January 2017. It's a two week long mini-event. It included 15 recruitable characters from 2016, with some battling bosses and others needing to be rescued from escaped villains.
Story 
Edit
The Avengers are Under Siege! Mephisto has manipulated Baron Zemo into freeing the Academy's imprisoned Super Villains, and our heroes have to battle the bosses to return them to their cells, and save their friends!
How to Play Edit
Collect Shackles from the Mission Board to battle the boss. Defeat the boss to earn Keys, which you can use to unlock the Under Siege Crate!
Characters Edit
These are characters that were obtainable during a prior 2016 event, but are now available to recruit again.
A-Bomb Edit
- 650 Shards
- Available to fight: Mephisto, Carnage, Ronan
Baron Zemo Edit
- 995 Shards
Captain BritainEdit
- 650 Shards
- Available to fight: Mephisto, Kingpin, Carnage
Dracula Edit
- 1 Tomato Juice (drops from battling Mephisto)
- 1,500 Credits
- Available to fight: Mephisto
Red Hulk Edit
- 650 Shards
- Available to fight: Kingpin, Ronan
Union Jack Edit
- 1 Starstone (drops from battling Kingpin)
- 1,500 Credits
- Available to fight: Kingpin
Black Knight Edit
- 1 chalice (drops from battling Carnage)
- 1,500 Credits
- Available to fight:Carnage
Punisher Edit
- Under Siege Crate
Winter Soldier Edit
- Under Siege Crate
Groot Edit
- Under Siege Crate
Blade Edit
- Under Siege Crate
Green Goblin Edit
- Under Siege Crate
Electro Edit
- Under Siege Crate
Jack O' Lantern Edit
- Under Siege Crate
Crossbones Edit
- Under Siege Crate
Bosses Edit
These are villains that were previously fought during a prior 2016 event, but are available to capture again. If players have previously captured them, they returned to their cages at the end of the event.
Mephisto Edit
- Drops Balls of Fire
- Drops Key Rings
- Mephisto's Cell costs 25 Balls of Fire.
Kingpin Edit
- Drops Baseball Bats
- Drops Key Rings
- Kingpin's Cell costs 25 Baseball Bats
Carnage Edit
- Drops Symbiote Components
- Drops Key Rings
- Carnage's Cell costs 25 Symbiote Components
Ronan Edit
- Drops Kree Emblems
- Drops Key Rings
- Ronan's Cell costs 25 Kree Emblems
Crates Edit
Under Siege Crate Edit
Training Edit
Utilize portals to train your fighters, increasing their attack and health skills. Each training session is seven hours long.
Power Portal Edit
- Trains attack skills
- Free at start of event
Vitality Portal Edit
- Trains health skills
- Free at start of event
Ultraviolet Portal Edit
- Trains attack skills
- Free with purchase of Baron Zemo
Event Horizon Portal Edit
- Trains health skills
- Free with purchase of Baron Zemo
Ultimate Power Portal Edit
- Trains attack skills
- Costs 195 shards
Incredible Vitality Portal Edit
- Trains health skills
- Costs 195 shards
Gallery Edit
