I'm currently doing a playthrough where it appears I'm working for both sides (NCR and Legion), but really I'm an NCR soldier that's infiltrating the Legion. I'm currently at the stage where I gain the Boomer's trust in order to get them to help me during the battle of Hoover Dam. The thing I'm unsure of is can I tell Caesar I've gained their loyalty in order to progress in the Legion's quest first, BUT tell Crocker after telling Caesar in order to get the Boomers to support the NCR instead. Will this work?

Also is there any way to kill Caesar whilst he's lying down without being detected? Would Mr Sandman work?

I really hope to hear someone that's tried this, because if it works, that's fantastic!

If you have a high enough medical skill and speech skill, you can kill him and say you tried to save him by botching his operation. They will get upset with you but you can talk them down. I don't recall if this gains infamy.

Would like to know the outcome as well. Either way, the boomers should support whoever you side with at the end of the game, not whoever they were pledged to.

You can botch his tumour op, BUT I think in order to get far enough in the Legion questline to actually do that, you would wind up failing Don't Tread on the Bear, which is the NCR's loyalty quest. In other words you can only do one or the other.

@IRORIEH wrote:

You can botch his tumour op, BUT I think in order to get far enough in the Legion questline to actually do that, you would wind up failing Don't Tread on the Bear, which is the NCR's loyalty quest. In other words you can only do one or the other.

True,

The quest "Et tu, brute?" is Part VI in the "Render unto Caesar" questline.

You fail "Don't tread on the bear" after Part IV, I believe.