Developer Page: argent
(dev id no. 5 - prev next)

Actually just seems to be a brand name used by Agenda. I should probably merge them, really. Collectively they've done a lot of pool and mahjong, and a couple of things for Nintendo and Sony, including DS game compilation "Daredemo Asobi Taizen" aka "Clubhouse Games", which seems to include pool but not mahjong. Probably because Nintendo already has its own stand-alone mahjong game, in the form of Yakuman DS.
Official Site:

Simple 1500 Series
The Billiard (with Success), The Billiard 2

Simple 2000 Series
The Billiard (Billiards Xciting)

Simple 2000 Ultimate Series
Urawaza Ikasa Mahjong Machi ~Oniisan, Tsukan Jimatta Youdane~

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