[{quoted}](name=Ice Weasel X,realm=NA,application-id=cIfEodbz,discussion-id=mYGXy7g2,comment-id=,timestamp=2015-12-16T23:40:05.561+0000)
As stated by Riot, the deals are based heavily on playstyle. Likely factors include champion type, lane, and role. They might also check data for previous skin theme purchases, or what types of champions you skin the most. The goal for this promotion is obviously to get people to spend some RP (and thus money), but merely focusing on your main champions would be very shortsighted. After all, pigeonholing you to your existing pool limits purchase options. By offering you champions (and skins) similar to your existing playstyle, they are encouraging you to branch out to possibly unfamiliar champions that you statistically may enjoy. Having more champions unlocked also creates more future sales potential for them since each champion has its own pool of alternate skins.