I think it's meant to be Shir's sole "secret technique" or whatever. Like Megido for Rolf.
While we're on the subject, the PS Pages doesn't seem to have quite all the techs characters learn IIRC. For example, I think Amy learns Gigra at some late point (or is it just Gra?), but they don't indicate this. So they're not entirely comprehensive either.
http://i40.tinypic.com/15yfy1v.jpg Mortal Kombat 3 Special 56 Pepoles: http://www.youtube.com/watch?v=8FY38b3cV5g