"retention" is a poisoned concept. if your goal is to maximize play time, you're exploiting your players. games should be made to serve people, never the other way round.
@jplebreton, maximize time? Maybe. That’s a covariate with what a publisher seeks.
Maximize likelihood of further purchase? Probably.
Maximize value added for other customers—as opponents, ‘community members,’ streamers, wiki-authors? Probably.
Server run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!