So the Containment War cards are limited edition cards ONLY available for 30 days, starting on the 28th October. Currently, the only way to obtain these is through very rare drop rates (0.3%) in CW equipment cases, or some-what rare drop-rates (10%) in the CW Elite cases.
However, the chance of getting a loadout you actually want (or for a merc you want) is EVEN lower than this, because of all the layers of RNG involved. We’ve also seen cases of people getting duplicate’s of the same CW card, which you can actually do nothing with right now. The actual maths for the case drops was worked out by a reddit user (I do not take credit for this, nor have I verified that it is 100% correct, but it looks reasonably so to me):
The actual drop rate for a CW card is 0.3%, meaning that statistically speaking you need to open more than 300 cases to get a single CW card - which is already more than most people open within 30 days.
And the final nail in the coffin is that even if I somehow manage to get a CW loadout (again, 0.3% chance), there is only a 1/17 (~5.9%) chance that this CW loadout is for the merc that I want, and then add to that a 2/9 chance that the card doesn’t suck (most mercs only have 2 viable loadouts).
This leaves me with a 0.003*(1/17)*(2/9) chance to get a usable card for the merc I want, which according to Wolfram Alpha equates to a 0.0039% chance, aka 1/25500, aka ONE in TWENTY-FIVE THOUSAND AND FIVE HUNDRED.
So… Would you like a trade-in option to get rid of your useless CW cards? My proposed trade-in would be 2 CW cards + 10,000 credits = 1 CW card for a merc of your choice.
DO NOT FORGET, TRADE-IN’S THEMSELVES SHOULD BE GETTING A PRICE/COST CHANGE IN THE NEAR FUTURE. Hopefully this will also happen before the event is over, so that we could also trade-in these pesky/useless CW cards. 
