Recently, it occurred to me that a max-duration Smoke Shadow (lasts 22 seconds) can easily be used to help a friend or an entire squad rank up frames and weapons quickly by coordinating invisibility, then chaining stealth attack bonuses on Ceres Extermination maps. I've done this sort of thing with Loki since ages ago, but never thought to use Ash.
The benefit is that whoever isn't playing Ash can bring whatever they want, or, if they're ranking up a frame, can bring a strong melee weapon and get their own kills for more frame affinity.
My good friend SaurusRex and I tested this today, and as expected, it worked like a charm. We saw 5,000, 8,000, 17,000 Affinity numbers popping up all over the place.
I'm interested in doing this with others, so if you have a bunch of stuff to rank up, hit me up by PM, in Discord, or in Clan chat.