Steve Vai has joined forces with Ibanez to create a new one-of-a-kind instrument called the “Hydra.” The instrument is “a one-bodied, two-headstock-ed, three-neck-ed creature that encompasses, among other things: 7 and 12-string guitars; a 4-string ¾ scale length bass; 13 sympathetic harp strings; half-fretless necks; single-coil, humbucking, piezo, MIDI and sustainer pickups; floating and hardtail…