This move is

,

,

+ (

+

). It requires a full 3 bars of shadow meter to activate, but can easily be knocked out (along with all the other Omen achievements except possibly the 85% damage one) in practice mode. Just set your shadow meter to infinite, walk over to the opponent, and do the above controller command in practice mode to unlock this achievement. The achievement is at 01:13 in the video below, which includes all the others as well.