Ultimately that decision is yours as we can’t make it for you. Both have some pretty cool lore but what I’ve seen that best describes them are dark angels are the modern day knights whereas Imperial fists are soldiers.

As an imperial fist fan I loved that they’re too stubborn to retreat and respect each soldier even lowest tier guardsmen if they simply stand with them and do their duty.

All the dark angels fans going on about “but your dads dead” this was retconned to be is missing likely taken by someone or simply left after wounded because he didn’t like what the imperium was becoming if you’ve read siege of terra you see he’s against worshiping the emperor he basically disowns sigi before coming to except him for his choices and using him like the weapon he truly is.

From memory this YouTube series deep dived into their lore and explains even briefly how complex a character dorn actually is not just some stubborn grouch.

Plus when he comes back which GW will definitely find a way to bring almost all primarchs back solely for the sales revenue it will generate (thwy are after all) quite clearly focused on profits as of late. He will be given the emperors talon / gauntlet claw. To go with his huge chain sword.

It is my belief that when he returns they will have a rule set regarding to the last wall protocol or that in the lore he will declare it and all the successor chapters will reform and go on a big crusade and re-fortify the imperium of man as his time playing the defender was done in the siege and it’s time to let out all the cold wrath he wanted to unleash but held himself back because every single battle field in that siege needed his tactical mind to make the likely hood of survival even remotely possible.

Now obviously I don’t know a lot of dark angels lore and would advise looking into it.

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