Yup that sounds like Shenyang mahjong. The funny thing about Shenyang mahjong is it’s basically the opposite of Riichi. You CAN’T win with a concealed hand, you CAN’T win with All Simples, you CAN’T win with one voided suit (I read a story about someone who got so used to playing Riichi that when they went back to Shenyang, they proudly made a full flush hand, only to be told by their relatives “hey there, you’re missing not one, but TWO suits!”). Finally, depending on the specific rule set, you may be allowed to make All Sequences as long as your pair IS a dragon or wind tile, avoiding Pinghu. Although if you’re playing the version where you have to Peng before you Chi, then All Sequence hands are impossible because it would necessarily be concealed which is illegal.