How does optimus prime die in transformers 2?

Ok in transformers 2 the fallen guy says that only a prime can kill a prime so if that's true how does megatron kill optimus if megatron is not a prime?How does optimus prime die in transformers 2?here is the movie clip were prime fights megatron :)

http://www.youtube.com/watch?v=oSo49BPYi…How does optimus prime die in transformers 2?
I think Megatron is an evil prime's descendant as Optimus is a good prime's descendant, but Optimus is revived and the whole a prime can only kill another prime thing really just comes into play with The Fallen vs. Optimus battle at the end. Meaning the only good Autobot who can kill The Fallen is Optimus. Anyway, Megatron could kill him because he is also a prime's descendant.How does optimus prime die in transformers 2?1st if you paid atention ther were at the bigingin 2 living primes (the Fallen) and (Optumis) No megatron is not a prime in the end ther was only one Optumus

He says brother to megatron because hes a fellow transformer

2nd

optumis dies frome a sword thru the hart wile fighting 3 others alone



P.S he comes backs and kick as$
In the first film, after Megatron falls, Prime says "You left me no choice brother."

Maybe in film continuity they are brothers.

Were they brothers in the cartoon series ?How does optimus prime die in transformers 2?Remember, Megatron is supposed to be Optimus' brother, so he is a Prime.How does optimus prime die in transformers 2?
Do you realize how many people you just ruined the film for?



Try to be more thoughtful before posting questions like this.
Megatron was a prime that turned bad. He killed optimus by ripping the cube out of his chest.How does optimus prime die in transformers 2?
he gets aids