I knew Shadowverse was popular, but its rate of growth is downright ridiculous. Back in February the developers celebrated 7 million downloads with 7 free card packs, and now a mere month later they're back at it again, this time around celebrating 8 million downloads!
As you can probably guess from the title alone, 8 million downloads means 8 free Rage of Bahamut card packs for every single player, new or old! However, instead of getting all 8 card packs at once you will need to log in five times over the course of the promotion in order to grab them all. The first login reward will give you 4 card packs, while the subsequent four will give you one pack each, as well as all of the standard daily login bonuses such as currency and classic card packs.
The promotion will last until March 28th, so don't stress about getting the card packs as soon as possible, they'll be here for quite a while. If you would like to learn more about Shadowverse, or just give it a try for yourself, you should head over to Steam. Have fun, and good luck with those legendaries!