The Clay Loogie is an attack used by the Blob in ClayFighter, it's update and C2: Judgement Clay. He lurches back for a quick second, then hocs a loogie that hurts if touched by his foe. Like a lot of projectiles in the first installment, It can hit you twice if close. This attack requires a quarter circle, which means you have to put your thumb on the down direction of the control pad, then quickly slide your thumb to the forward direction or the backwards direction. Then you have to press the button required to make the move work. In this case, you have to press down forward punch (any strength will do) in order to use this attack.
This move also was performed by his evil clone Slyck in C2, but called as Psycho Spit, and can be performed in the same way than Blob.