Hi guys, I have a theory regarding Ben's death. Note: this will contain some information from Seasons 1 and 2, and the comics so if you are planning to watch/read any of those and don't want spoilers, just keep on scrolling and do your thing :D

I'm going to split this into parts: Character Studies, Basic clues/info, Guilts, and finally, what happened

Character Studies

• Luther

- Luther is the leader and tended to tell Ben to do things more.

- Ben is described as "easily-manipulated" and constantly wanting to please Reggie-boy and Luther.

- In the bank robbery scene, it's Luther that tells Ben to go in the vault.

- Luther's the leader to the blame could have automatically been shifted to him.

• Diego

- Diego has a tendency to be rough with his siblings and forget filters. This is shown during Ben's funeral where he flat out tells Vanya she wasn't on the mission and has no clue what she's talking about.

- However, we know that Diego did care for Ben, as seen in Season 2 when Ben possesses Klaus and talks to Diego for the first time in 18 years

• Allison

- Allison's powers consist of mind control. She can easily rumor anyone as long as she's able to speak.

• Klaus

- Klaus doesn't seem to usually fight during battles. The extent of his powers (as of right now) wouldn't be useful in battle.

- Klaus, at the time, was drinking. At Ben's funeral, when he brings him back he takes a drink out of a flask.

- Klaus also has a tendency to get distracted on missions, as told by Allison to Claire during her bedtime story.

• Five

- Five is an exception as he wasn't there during Ben's death.

- This is proven because when Five time traveled to the apocalypse, Ben was at the table.

- Also, Five was not at Ben's funeral.

• Vanya

- I think Vanya was close with Ben and Five. It explains why they're so understanding with her whenever they interact.

- Vanya was the only one crying at Ben's funeral before Reggie-boy started going off (then most of them started crying, father of the year am I right?)

- Vanya doesn't go on missions

Basic Information/clues regarding Ben

- Gerard Way said that they all have some sort of blame regarding Ben's death

- Ben was most likely killed on a mission. Many people say it might have been suicide but this is not an option, as Diego told Vanya she wasn't there during the death which implies the rest of the kids were

- Ben's power isn't just a mutation. He can open a portal to another dimension from his stomach. This dimension happens to be where the octopus tentacles are from.

- We have no idea if Ben has any control over the tentacles, BUT I believe he has no control. Again, it's a portal to another dimension so that's essentially another creature. Plus, Ben is timid and would not murder people as gruesomely as he did

- Ben clearly dislikes missions and doesn't wanna be on the team

- Ben's ghost form comes to Klaus as normal rather than how he looked when he died

- Octopi revert to cannibalism sometimes due to stress

How the siblings may have been involved/guilts

• The team had a mission and before hand, they discussed a plan. Ben was most likely told by Luther to do something he didn't want to do. Before they left, Ben ran into Vanya and asked her about it. She said it may be a better idea to go with the flow, which is where Vanya's guilt would come from. Vanya feels like she could have initially stopped Ben from doing it.

• On the way to the mission, they were probably trying to convince Ben to do this thing. Diego probably was extremely harsh with Ben, which would cause regret later on. That's where Diego's guilt comes from. Diego feels awful about treating Ben that way on the way there.

• Luther most likely told Ben he had no other choice but to do this thing. Luther definitely knew his place as number one, and he knew Ben knew that. That's where Luther's guilt would come from. He feels if he hasn't come up with the idea and used his authority to force Ben, Bsn wouldn't have died.

• Klaus, even though he didn't have too many strong powers while fighting, was definitely trained in physical fighting. I think Klaus was assigned to Ben as a partner and was either drunk, distracted by something else, or both. That's why Klaus feels guilty. He feels he could have backed Ben up and saved him.

• Finally, I think Allison may have rumored Ben, which would explain why she resents her power (other than losing Claire)

What exactly happened?

As a 13-15 year old, this clearly was a high stress situation (well, it was worse than usual). Ben, after being rumored was so horrified at what he had done, that instincts kicked in. The tentacles could sense this feeling and reverted to octopus instinct. As I mentioned earlier, octopi revert to cannibalism sometimes due to stress.

In conclusion, I think Ben was either torn bit by bit or eaten alive by the monster within him (which would explain his inscription on his statue)

Ah, the urge to push the delete button on life.

I imagine it to be big and square and loud and instant.

Drawing me in, enticing the soul, a dare to throw the dice.

All it would take is a nano second to push,

The smoothness of the key as it loosely wobbles under my index finger.

Would it be a restart? That doesn't wet my appetite

I run on emptiness and caffeine, some whiskey or gin.

A delete me seems inevitable, who would care? Who would win?

It seems logical, the only way... it must be right.

Delete me and the program ends. A cold shutdown. No more light.