Mahjong Club

Steam has tons of Shanghai mahjong tile games but those ain't real mahjong. Mahjong Club is one of a few that is the real deal mahjong game. Despite some bugs, the gameplay is surprising good. Every character in the game has their own special ability and perks that are naturally inclined towards having advantage over the outcome of their hands or favour towards a certain of play style, or having a higher chance of drawing a particular class of tiles, or gravitating towards a certain yaku. The anime-ish characters and their abilities and skills resembles the counterpart from the characters of the Saki anime. It reminds me of the gameplay of some character's special skills somewhat similar to the Saki mahjong games on PSP/PSvita, such as Saki's trademarked special mahjong skill, "Rinshan Kaihou" or the "Dead wall draw". A plus is that Mahjong Club is beginner friendly to those who are new to mahjong. It has a nice beginner friendly tutorial and practice drill to introduce newcomers to the basics of mahjong and yakus.

Abandonware and buggy there are a lot of free online tools/games that work a lot better than this. but it's okay for single player

Abandoned by developer, some achievements at least nearly impossible to get. Obviously do not buy this.

I had fun playing with friends despite some bugs, it feels like playing saki

This game is... fine. It feels like more effort went into the menu screens than the game. Play angle is weird. Translations are weird, ranging from "sounds like" translations for riichi (reach) to clunky translations for yaku and even stranger machine translations for dialogue. There are free alternatives that do a better job at teaching the game, from scoring to strategy.

A mahjong game with abilities/superpowers, and a game baring similarities to the 'Saki' franchise. It's good to play with friends, and is a nice break from regular mahjong. Encountered a few bugs in multiplayer, but solved quickly. (crashing stops once the victim hosts a game once.) Gameplay has pretty bad balancing issues, but it's all fun and games with friends. It's a pretty barebones game, and there are better mahjong clients out there, but it's definitely a game you should try if you have a group of friends who enjoy mahjong, and if you want a change of pace.