Why not give every champion a unique pose or something as the final reward for this system. It would take a bit of time to set up because obviously there are alot of champs but id much rather see this come out in the future and be complete the come out in a few patches and be shit and nobody using it or caring because u guys rushed it for quick cash. The only reward I think that is going to get people to even pay for this shit is to make each champion have some sort of cool unique pose or something they can do for looks in game after u complete the achievement. It would take some design work to do but it would at least make it actually fucking worth and would actually encourage people to pay the rp hell id pay 10 bucks for a cool in game champion pose for my main upon completing the achievements. As is tho ur actually wasting alot trying to make this system as i see nobody paying anything for this shit. Don't be lazy Riot. Take your time with the release of this and do the work and reap the reward. :)
In reality Riot. You're making people pay a chunk of cash for a few bars about the mastery emote that most people have turned off on the enemy team and wont see because they dont wanna get tilted by it and you dont even immediately get it. So you're making people pay money for a few numbers on their screen that track when they do things on their champ, techinically i could keep track of this stuff myself its not showing anyone until i get the emote and even then most people have that turned off on enemy team. You guys are actually putting 0 effort into this expecting to get a quick cash grab for a few bars above the mastery emote thats stupid.