History
This device was developed by Doctor Doom and could be optionally incorporated within his armor,[1][2] its single operative unit being kept at Castle Doom's labs the rest of the time.[2] The device sent a bolt of energy that could bore through ground of stone or mud making absolutely no sound.[1][2] It could create a tunnel of up to three meters of diameter, slowly creating the tunnel.[2] It could also be reconfigured as a weapon to attack nearby enemies, but the process required manual resetting.[1]
At one point, Doom travelled to the Hydrobase research center in his Amphibious Skycraft to help rescuing his prospective ally the Sub-Mariner from the later's enemies Attuma; Doctor Dorcas and Tiger Shark. Doom did not reached the place undetected - Dorcas's sensors identified the ship and Doom had had an encounter with Attuma's troops. Thus, Dorcas and his cronies were alert and decided to ambush Doom at the Sub-Mariner's cell, his obvious target.[1]
Doom meanwhile allied with Sub-Mariner's friend-with-benefits Betty Dean Prentiss, who told Doom where was Sub-Mariner being held. Doom used his Sonic Drill to reached the underground cell, but once there he and Dean Prentiss found that the enemies were waiting for them. However, when the tied Sub-Marined distracted the enemies' attention, Doom quickly reconfigured the Drill and turned it into a weapon that stunned Attuma and Shark.[1] Doom eventually released the Sub-Mariner and escaped with him,[3] although they were unable to save Dean Prentiss.[1][3]
No longer after that, back in Latveria, Doctor Doom was ambushed by up-and-coming superhero Shroud. When Shroud dodged Doom's Fingertip Darts, Doom decided to try the Sonic Drill against this foe. However, Shroud was quicker than Doom and threw parallo-mist to the Doctor before Doom could use the Drill.[4]