Rolling Thunder

Rolling Thunder is a series of side-scrolling action games developed by Namco. The player controls "Albatross", a secret agent for the WCPO's "Rolling Thunder" espionage unit. In the first game, he must rescue his female partner Leila from a terrorist organization named Geldra, led by an alien named Maboo. The second game featured a co-op mode where Leila and Albatross stop Gimdo, who has revived the Geldra terrorist group. The third game takes place during the second game and it has the remaining agent Jay go after the second-in-command Dread.

Unlike other action titles, it is a little more slower paced, and is more about strategy and conserving ammo than mindless running and gunning. You often have to find cover, hide behind doors (Some of which held ammo for your weapons) and leap up and down between floors.

This series only has three games, the first two starting in arcades before being ported to home systems, and the final game being released only on the Genesis.

Rolling Thunder: 1986 (Arcade), 1989 (NES)
Rolling Thunder 2: 1990 (Arcade), 1991 (Genesis)
Rolling Thunder 3: 1993 (Genesis)

There is also an officially sanctioned webcomic, Rapid Thunder, that continues the plot of the games.

Not to be confused with the unrelated 1977 action film of the same name.

Tropes used in Rolling Thunder include:

Action Girl: Leila in Rolling Thunder 2. Ellen is also playable by a cheat code in Rolling Thunder 3.
Adaptation Expansion: The Genesis version of Rolling Thunder 2 added three extra stages where you get exclusive new weapons and fight new bosses.
Aliens Speaking English: Dread in the third game, which is the only one to have cut-scenes with dialogue.
Awesome but Impractical: Hiding behind doors. Besides wasting time, enemies will keep appearing and sometimes they will stay around the door until you come out. The second game required this in the last level, but that's only because you need to conserve ammo for Gimdo, the final boss. Unless you like firing Painfully Slow Bullets...
Big Bad: Maboo in the first game, Gimdo in the second.
Blatant Item Placement: The doors that supply you with more ammo when you enter them. You can easily tell there's one when a sign is nearby. Some doors also hold time bonuses and extra health, but those are less obvious.
Blush Sticker: This happens in the NES version of the first game when Leila kisses Albatross on the New Game+.
Bottomless Magazines: Averted with everything but your pistol. If your pistol runs out of ammo, you'll fire slower "ghost bullets" until you find more ammo or die.
Bottomless Pits: There's none in the third game, thankfully.
Captain Ersatz: Maboo looks a bit too much like Piccolo Daimaoh, while his successor Dread resembles the reincarnated Piccolo wearing a monocle.
Chain-Reaction Destruction: Some robot bosses in Rolling Thunder 2 and Rolling Thunder 3. Rolling Thunder 3 also had the cracker grenades which explode this way.
Code Name: Your agents.
Collision Damage: The only damage you can take that isn't a One-Hit Kill.
Continuing Is Painful: Woe to you if you die, you'll go back to your pistol and lose any extra ammo and your machine gun (if you had one) when you restart from a checkpoint, or worse, the whole level. Rolling Thunder 3 averts this problem by resuming from where you die, thankfully, and you keep everything you have (unless all your lives are lost).
Crosshair Aware: The sniper and spider robot in the third game. There's also the first and third bosses of the Genesis version of Rolling Thunder 2.
Damsel in Distress: Leila in the first game.
Denial of Diagonal Attack: Played straight in the first two games, but averted in Rolling Thunder 3, where you can fire at an angle and in midair. This only works with your pistol though.
The Dragon: Dread in Rolling Thunder 3.
Easy Mode Mockery: Played straight in all three games. In the original arcade game, when you beat the first five stages, Maboo laughs at you and you go through a Hard Mode Filler. The NES version, along with both Genesis games, gives the player a password after completing the normal difficulty which restarts the game on a harder setting. The full ending of each console game can only be seen by completing their respective hard modes.
Elaborate Underground Base: All games have at least one, but the first one was pretty much where it took place.
Evil Laugh: Maboo does this when you either get a Game Over or complete the first five levels.
Floating Timeline: A weird example. The first game was an intentional period piece set in the late 1960's, but Rolling Thunder 2 moved the game's setting to the 1990's. The sequel even establishes that it's the same Leila and Albatross from the original game, not just successors inheriting the same codenames.
Goomba Stomp: Starting in the second game, jumping onto an enemy will knock him back and briefly stun him without damaging you, making this a semi-legitimate attack.
Hand Blast: Maboo in the NES version of the original, Gimdo in the Genesis version of Rolling Thunder 2, and Dread does this in the second phase of his final battle.
Hard Mode Filler: The latter half of the first game, which feature redesigned versions of the first five stages with more elaborate traps (except for Area 9, which is entirely original).
Kill It with Fire: The Flamethrower weapon in the Genesis version of Rolling Thunder 2 and Rolling Thunder 3.
Life Meter: The arcade version's was pretty ridiculous. Your life gauge had eight bars when your character actually had only two hit points. Getting shot once killed you, and touching an enemy decreased the life gauge in half. This was corrected in the arcade sequel and all the console versions.
- In Rolling Thunder 3, you get three hit points if you play on the normal setting, but the harder difficulty gives you the standard two hit points. Some unmarked doors actually have life expansions. Or the special weapon door if you didn't pick an alternate weapon in the pre-mission menu.
Load-Bearing Boss: After killing Dread in the last level of Rolling Thunder 3, he tells Jay that a self-destruction mechanism is wired to his heart and destroys everything in the base, including Jay. When you beat the game on the "Hard" difficulty, it's confirmed that Jay survives, though you can probably tell from the silhouette during the credits where he rises from the rubble.
Mooks: The Maskers in all three games. The sequels turned them into Mecha-Mooks, possibly due to them resembling a certain hate group...
- But they look FABULOUS!
Mini-Mecha: When you face Dread for the second time in the last level, he fights you in one in his first phase.
Mission Control: Ellen in Rolling Thunder 3. A cheat code makes her playable.
Nintendo Hard: Especially the first game.
Nostalgia Level: In Rolling Thunder 3, one of the secret stages is an abandoned cobweb filled version of the first level from the original Rolling Thunder.
Not Completely Useless: The knife in Rolling Thunder 3. Not only is it helpful for close range combat, but it's helpful against Dread's second phase in your final encounter with him.
One-Hit-Point Wonder: Getting shot even once kills you. Subverted in Rolling Thunder 3 in that you die in two shots unless you play on the Hard setting.
POV Sequel: Rolling Thunder 3 takes place during the second game, where Jay goes after Dread, Gimdo's second-in-command.
Respawning Enemies: The Maskers keep coming out of doors constantly.
Robotic Reveal: Gimdo in Rolling Thunder 2.
Shock and Awe: How Leila is tortured in the arcade version of first game.
Stalked by the Bell: In Rolling Thunder 3, a sniper appears and fires at you if you take too long to finish a level.
Take Cover: One of the earliest games to use this mechanic.
Timed Mission: The first two games.
Villain Exit Stage Left: Applies to Gimdo in Rolling Thunder 2, where he gets away in a sub at the end of the first half. Dread does this a couple of times to Jay in Rolling Thunder 3 as well.
"Wake-Up Call" Boss: The robot boss in the Genesis version of Rolling Thunder 2. His crosshair will slowly move back and forth and fire at you. Unless you can take advantage of a certain blind spot close to him early on in the battle, you'll lose a few lives and see the continue screen once or twice until you figure it out.
- The third game's first boss isn't any better. It'll move back and forth and fire shots at you, and will also jump in the spot where you're currently standing. What's worse is that when half of it's health is gone, it'll switch to a crosshair which fires explosive shots.
A Winner Is You: The first game's ending when you finally kill Maboo. The other two are a little better, but not by much.
With This Herring: You always start with a pistol with limited ammo, and have to find more ammo or other weapons (usually a Machine Gun) behind doors. Rolling Thunder 3 gave you a knife if you chose not to start a round with any special weapons.
You Gotta Have Blue Hair: While Leila is a brunette in the actual game, the promotional illustrations for the first game and the packaging illustration for the Mega Drive version of Rolling Thunder 2 depicts her with blue hair.