Super Vanishing Beam
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Super Saiyan 3 Gotenks had used his Volley Ball attack on Super Buu and spiked him deep into the ground. While in the crater, Super Buu held his hand up in a fashion identical to his Genocide Blast attack. He unleashed an enormous purple beam that filled the entirety of the crater and blasted up into space narrowly missing Gotenks, who had been peering down into the crater.