When GM Liu was very young, before he met Li Shuwen, and was also in frail health, the family body guard taught him 2 forms of Mizong Yi and a very long and slow form of Taizuquan.
This form has been around Wutan schools for quite a number of years (at least 20 years back in Ohio, maybe longer)
https://www.youtube.com/watch?v=oBhLh7u2yLs
https://www.youtube.com/watch?v=POFrlyu4sPM