I’m missing a half dozen or so legendaries. I know it’s really RNG but I’m trying to figure out the cost-benefit ratio for Gem chests vs. VIP chests.
I know VIP chests have a much higher payout per chest. On the other hand, I can open 50 Gem chests for the cost of just 10 VIP chests.
In my situation, where should I be spending my gems?
It’s hard to say for sure as we don’t know the exact drop rates but it seems almost certain that VIP Chests are better across the board. It’s around a 5x drop rate on Epics and Legendaries and a 10x drop rate on Arcanes and Mythics. Plus you get 2x Epics/Arcanes for each drop. The only thing you don’t get more of from VIP Chests is Ultra-Rares and Runics.
Thus, you’re probably breaking even on Legendaries overall, but you’re getting way more of everything else while you’re breaking even on Legendaries.
Vip, vip, vip 
You could also wait for the Kingdom event to come around and throw 100 or so keys at the event chests. You’ll get less overall return, but a much better chance of targeting what you seek.
Three Hail Marys and an Our Father.
Hey @Tacet, could you weigh in here. Watching your video last week, it seems you might think Gem keys are the better value over VIP keys because of the cost vs. benefit ratio…
He’s already weighed in on this topic.
Man I searched for stuff before I posted this thread and never found that. THANKS!!!
So if I was trying to get the new mythic troops I need to focus on the VIP chests instead of the gem 
chests correct
VIP chests are more efficient/effective if you are explicitly targeting Mythics and don’t care about the other rewards.
I still need several legendaries (and still have quite a few epics to ascend) so from now on I’ll be opening more gem chests until I get that done.
What do I use for VIP chest for example like I use glory for glory chests
You open a VIP chest with 50 gems.
Okay thanks