As far as arcade shooters go, Thunder Dragon 2 is relatively simple, with uncomplicated scoring and secrets and a straightforward ranking system. Enemy bullets are harder to see than in most shmups, due to blinking white and blue. In the latest version of MAME, the bullets are also erroneously set to a lower sprite layer, which means they will often be hidden by the numerous explosions on the stage. Many of the enemies shoot targeted shots, so movement is necessary and a high premium is put on stage memorization for both scoring the surviving.
Controls[edit]
Controls for the game are simple, it's just a joystick and two buttons.
- 8-way joystick: Move your plane around the screen. You can move in any direction.
- Shot button: This button controls your plane's main weapon. Your main shot is a short burst, so you will need to tap the button to continue firing, or set it to auto-fire.
- Bomb button: The bomb creates explosions over the entire screen and cancels enemy bullets. There is hardly any delay, so this can be used for panic defense as well as strategically.
Scoring[edit]
You will earn points by killing enemies, with harder ships giving you a better score. Additionally, collecting medals will help you to boost your score. There are four medals ranging from 500 points to 50,000 points. Some medals can be uncovered by shooting at certain portions of the stage and others are left behind after taking out enemies or groups of enemies. The 50k medals require the most complex actions, and depend in large part on how quickly you can defeat the stage. Using a continue will reset the score to zero.
| 500 medal | 1k medal | 10k medal | 50k medal |
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At the beginning of each stage are letters which are worth points and if you destroy them all you normally receive a bomb. The exception is on the first stage where you get a 50k medal. All medals are worth a set amount, except for the 10k medal which increases by medal chaining. The chain will increase from 100 up to 10k and won't be broken by missing a medal. The chain will, however, be broken if you die.
Planes[edit]
There is no health bar for the planes; they take only one hit to perish. You start with three lives and there are no extends in the game. The player 1 plane starts out on the left side of the screen and all its information resides there also. The opposite is true of the player 2 plane. Your bomb stock is displayed at the top of the screen below your score with a 
icon for each bomb you have, up to ten. You start the game with three bombs in stock and your stock is reset to this number if you die.
Player 1's plane is slow but powerful. It shoots a spread of laser bullets in a "V" formation from the front of the ship. As power-ups are collected, the plane will add bullet streams and power. The player 1 plane uses missiles that shoot straight up from the plane. This plane is best suited to high scoring, due to the quickness with which it can dispatch enemies and bosses.
The player 2 plane is much faster, but has a weaker main weapon. This plane shoots a nearly continuous stream of tiny laser beams in a straight line up the screen. As the plane is powered up, the laser stream gets wider, starting at approximately the width of the ship and growing to nearly twice as wide. The player 2 plane uses homing missiles that seek the nearest enemy ship. This plane is best suited for survival, as it has high maneuverability and the homing missiles can help take out snipers.
To power up your planes, you will need to collect power-ups and missiles. Power-ups are marked with an orange "P" and missiles with a blue "M". The power-ups will increase the efficacy of your main weapon through four levels of power. Missiles will add four missiles to your arsenal, which are fired intermittently with your main weapon.
| Power-up | Missile |
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Rank[edit]
Rank increases by powering up your plane and surviving. Rank is not explicitly tracked, but there is a noticeable increase in enemy aggression as your rank increases. Although dying will reduce your rank, there are no extends in the game, so this tactic is generally not worthwhile, and if the game becomes too difficult, you will die anyway.