R-Type games

Availability: Through R-Type Dimensions EX
Chronological Year: 2163
This is where the war between humanity and the Bydo begins.

Availability: Through R-Type Dimensions EX
Chronological Year: 2165
The Bydo have returned! Set two years after R-Type,
you must fight the Bydo AGAIN in 6 more deeply warped stages.
This game introduces the second charge shot seen in all games onwards.

Availability: NSO (regular)
R-Type II, now on the Super Nintendo.
Fly the War-Head through 7 hellish stages to vanquish the Bydo.
This game is a lot harder than the original R-Type II.
While the stages have been arranged... this game has NO CHECKPOINTS, PERIOD.
Also this game has the worst amount of slowdown out of any R-Type game.

Takes place alongside R-Type Delta.
This game is more speed orientated as the closer your ship is to the right, the faster the game goes, the further in the back you are, the slower the game goes.
Availability: [N/A] (This game has not been ported yet.)

Availability: [N/A]
Chronological Year: 2163
Planet Eden, a Man Made mechanical planet, is taken over by its own supercomputer core, Major.
You must destroy that core.
This one was originally a different game made by Nanao before being retooled into an R-Type game by Irem, hence why some things operate differently.
In fact, your experience with this game will differ greatly with what region you choose to play this game in.
If you pick the JPN version, you only have one button to attack, traditional checkpoints, and you must charge to use your pods.
If you pick the WORLD version, you have two buttons to use, and instant respawn.

Availability: Through R-Type Dimensions III
Chronological Year: 2169
The Bydo's back for the third time.
This game introduces 3 different Force Pods,
all with different sets of weapons.
It also introduces an Overdrive System that lets you
fire unlimited Charge Shots for a short time.

Availability: ???
A 1:1 REVERSE ENGINEERED Remake of R-Type 1 & 2.
Outside of it being a remake,
it features LORE with the R-Museum.
This game exists for financial reasons and for
the team to familiarize themselves with the
PS1 hardware so they could make R-Type Delta.

Availability: Through R-Type Delta: HD Boosted, Steam, PSN Store, eShop
Chronological Year: 2164
The first 3D entry.
This game introduces the Delta Weapon. A screen nuke that accumulates energy
from your Force Pod making contact with the enemy
This game also introduces the manual speed change system from Image Fight.
Finally, this game has multiple endings depending on which ship you choose.

Availability: Amazon
Chronological Year: 2183
This game brings as many ships in as possible for one FINAL Battle against the Bydo Empire.
This was intended to be the Grand Finale of the R-Type games. But as fate foretold, this wasn't the Curtain Call for the franchise.
In this game, some stages will be different depending on what ship you pick, or your own actions throughout the area.
There are also several callbacks to other Irem games.

Availability (for Dimensions EX): Steam, Xbox Store, PSN Store, eShop
A more modern 1:1 Remake of R-Type 1 and 2 with an optional 3D Mode.
This game lets you pick between Classic Mode (Lives & Checkpoints) and Infinite Mode (instant respawn & no lives).
This game is the most beginner friendly way to get into R-Type.

Availability: Arcade Archives, Irem Collection Volume 1
Chronological Year: 2249
R-Type but if it was inside a human body, and the Force Device was replaced with Tentacles.

Availability: Steam, eShop, PSN Store
Chronological Year: MC0065 (Tactics I) & MC0074 (Tactics II)
R-Type enters the War Games with the Bydo.
Perhaps, the most story driven R-Type game.
This one isn't a SHMUP, but a War Simulation Game with hexagon tiles.

Availability: Arcade Archives, Irem Collection Volume 1
Chronological Year: 2048
This is a vertical shooter with almost the same mechanics as R-Type but with major differences.
This game allows you to manually adjust your speed.
There are 5 Image Stages and 3 Real Stages, 8 in total.

Availability: Irem Collection Volume 3
Tame your dragon, Bahamut and take off against the people who are against the protagonist, Kayus, becoming king.
The Dragon is invincible, but you aren't.

Availability: Irem Collection Volume 1
Chronological Year: 2051
Image Fight's Sequel that's way harder and has way more bullshit going on.
Instead of going through 8 stages, you now have 10.
Have fun.

Chronological Year: 2043
This is a 3-Player post apocalyptic beat em up where you play as the city sweepers, Zan, Matt, and Rose, who have to stop organized crime and defeat the evil organization D.A.S. (Dark Anarchy Society).
One of the score items that can be found is a TV playing R-Type.
After this game, Matt Gables would later go on to pilot a Gains in R-Type.
Availability: [None] (Limited Run Games had it until they ran out)
Otherwise, this game currently has no other ports.

Availability: [None] (This game has not been ported yet.)
Chronological Year: 1999
This is a post apocalyptic fighting game with its connections to R-Type being the Final Boss being controlled by the Bydo.
This game is wild but also not very good.

A very blatant R-Type clone, but fun fact, because of how close to R-Type this game was, Factor 5, the developers was forced to make the Amiga port of R-Type.

Availability: Arcade Archives
Chronological Year: 2191
Defend the Earth from invaders in a ship armed with Variable Armos and Weapons Systems.
This game is very blatantly an R-Type clone.
The pods being aimable is a neat idea but this game has terrible music.

Availability: Arcade Archives
Chronological Year: 1991 AD
Defeat the galactic evil overlord Klaus Pachel Bell and save the princess of Planet E-Square, Irene La Tias.
Just like R-Type Leo, this game plays differently depending on which version you play.
If you play Orius (INT), you will have way less weapons but instant respawn.
If you play Xexex (JP), you will have more weapons but checkpoints.

If you're curious on the specifics of what exactly is different in this game, see: shmups.wiki/library/Xexex for more info.

Availability: Arcade Archives
Chronological Year: 2248
Blatantly an R-Type clone, but with 3D pre-rendered graphics.
A rumor says that this was made by former IREM devs, however that's merely a rumor and has yet to be proven true.
You can choose whatever stage you can start with, but after you beat it, you must progress in a set order.
Because of those graphics mentioned, the game does slow down a bit, but not to an unplayable degree.
This one is notably harder than any other game listed here.

Availability: Arcade Archives
The Sequel to Pulstar.
Like R-Type Delta, you can select different ships to pilot. However, there is no Force Pod to protect you, and there is no level select.

Availability: Arcade Archives
Chronological Year: 2990 AD
A rumor states that this game was made by former IREM staff.