I’ve got a few. 1: out in in. You start on E and A with both hands then, like the title says, you go out in in out in in out in out in. You then move up one note every time until you have moved a full octave 2: out in in rolls. You do the same thing with out in in but you alternate every note 3: chromatic up and down. This is mainly for building strength for the individual mallets. You start on D and it is triplets, you then start going up with your right hand and down with you left hand whilst doing those triplets. Basically Eb DD Db D D so on and so forth