Thunder Dragon © 1991 NMK.
Main CPU : Motorola 68000 (@ 10 Mhz)
Sound Chips : YM2203 (@ 1.5 Mhz), (2x) OKI6295 (@ 24.242 Khz)
Screen orientation : Vertical
Video resolution : 224 x 256 pixels
Screen refresh : 60.00 Hz
Palette colors : 1024
Players : 2
Control : 8-way joystick
Buttons : 2
Released in August 1991.
Licensed to Tecmo for distribution.
A bootleg version uses the "Raiden" (seibu) sound hardware (a Z80 @ 3.579545 Mhz), all musics from "Raiden" are present =).
* Secret Message : Reset game and hold down Player 2 buttons 1 and 2. If you did it fast enough, you will see the message 'Ready?'. If not try again. Press P1 Button 2(x14). If you did this correctly, you should see another message '4th June. 1991'. And you are in the test mode.