Reply To: Noob help wanted with 40k Space Wolves

[amachan 25677xp 1]

Within a detachment, yes-ish. They can be from different chapters but I would recommend that they are at least successor chapters or the original chapter, like Imperial Fists. This gives you the chapter bonus. You can mix and match Space Marines with other chapters as you like, just be sure that in any detachment all units share a faction keyword other than Imperium, full list is in the big FAQ 2 from 2018. You can mix different factions with different detachments, like a Space Marine detachment and a Tyranid detachment and your army will still be Battle-Forged.