From the blog "Kill Team - Outreach"
Long story short, I'm preparing to play a game of the 2021 edition of Kill Team with three players who have never played any edition of Kill Team. We're going to adapt the Joint Ops rules from the current edition of Kill Team, sort of. The Joint Ops rules allow each player to take half of their normal kill team. This works fine with most of the factions since they use two fire teams - each such player would only use one fire team. Each of the Space Marine kill teams, however, consists of a singl