Hmmm... 4 40% capture rate familiars thought I was cool. I tried to persuade all of them. This was on heroic mode(+200% capture rate) and during the Saturday bonus(+30% capture rate). I also tried to capture 5 20% obtain 5 20% capture rate familiars. Out of all of them, none joined my team.
If you get one of those ad crates just close the ad after you open it. You'll get the rewards. For those of you with an adblocker, I think playing in an incognito tab(Ctrl-shft-n on chrome) makes it work.
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