Hearthstone is an awesome free game to play, Taiwanese are fully into it so is my gf even tho its an american company they have all different languages. Very popular all over the world and only a few years old.
Its bassically an interactive card game where you play your cards/creatures and they attack your opponent or your opponents creatures and some cards have massive synergy and cool effects. you start with 30 health and so does your opponent first one to kill them wins.
they also have tournments 100k for the winner.
Remember when you where a little kid and use to get crabs to fight each other or ants or whatever it kinda feels like that but with strategy like chess and luck like poker.
Also poker is pretty good game and free and starting to grow some momentum here in taiwan.
Taiwanese play chinese poker and i recently taught my gfs father and mother how to play and they where reluctant to play and associate it with evil gambling game where you lose all your house but then they preffered texas hold em over there style of poker.
So poker/texas holdem should be able to grow here very rapidly especially with the opening of the casino in a few years and big companys like pokerstars have there eyes on taiwan.