Version 5.6 is now available!

🔥 Level 4 Fully Reworked

Level 4 on Slyana has been completely redesigned. Originally meant to be a Boss Rush stage, it lacked intensity and consistency with the first three levels. I added an additional mid-boss and reworked the entire stage: enemy movement patterns, background design, and overall level flow.

The atmosphere now matches my original vision — an open-air arena where wealthy Slyanians bet on space battles.

Space gladiators wage a merciless battle here

🚀 Improved Rynex Sprite

Since the very first versions of my game, I’ve been using the Rynex sprite sheet from Thunder Force IV. The problem is that the style of that sprite sheet clashes heavily with the style of the background and enemy sprites. So I integrated a graphically enhanced version of the Rynex ship.

Better, isn't it ?

🎯 More Forgiving Collisions

Player hitboxes have been adjusted.
This was a long-standing engine issue related to angular bullet trajectories. After feedback — including from a Japanese YouTuber who played the game — I fixed the problem. Collisions now feel fairer and more accurate.

Your flames no longer frighten me, for the developer has coded more forgiving collisions

💬 Improved Cutscenes

My cutscenes had a problem: unless you paid very close attention to who was piloting which ship, it was difficult to know who was speaking. It was also unclear whether a character was thinking or speaking out loud.
I found a simple solution: adding dialogue bubbles above the ships. If the speech bubble is transparent, the character is thinking. If it’s solid, the character is speaking.

Who’s speaking? No more excuses — now we know 🙂

Woa, thank you very much!

Taking the time to create an account just to leave your feedback gives me burning motivation to pursue this project.

I update the game regularly, and a big update is coming in the next weeks (with one new level) — hope you will enjoy it :)

Since you found this project through Thunder Force IV discussions on Reddit, you must be a real fan — I’ll make sure to keep the spirit alive.

Stay tuned, more surprises are on the way!

Update 5.1

Here’s the link to play it: https://triganov.itch.io/thunder-force-heaven

And here it is — Thunder Force VII: Corrupted Thunder version 5.1 is finally out!

This new update builds on the big leap I made with version 5.0. Back then, the biggest improvement was in level design. Up until that point, I was creating levels straight from my head. To improve the difficulty curve and make the game more fun, I started designing and sketching enemy and obstacle sequences before coding them. Total game changer!

I also extended the level length: instead of short stages capped at 1 minute and 30 seconds, levels now run 2 to 3 minutes.
The entire game now runs at 640x480 resolution (no more 640x400 or even 300x200 leftovers). This gives the game a cleaner and much more appealing retro look, straight out of the Sega Genesis era.

Controls were reworked too. I realized how convenient it is to use the W, X, and C keys to switch speed, shoot, and change weapons — and of course, gamepad support is still there. On top of that, the collision system has been adjusted: it used to be merciless with the player… not anymore.

However, version 5.0 had its share of issues:

• Several gamepads were not compatible.

• The two levels lacked enemies.

• And most importantly… it was missing something crucial: SOME PURE CARNAGE! 🎶

That’s why version 5.1 is here. At first glance, it might not look like a big change, but it’s actually a major improvement.

Of course, I fixed the gamepad compatibility and the missing enemies. But the real highlight is a brand-new gameplay feature:
BURSTING THE CLAWS.

Bursting the claws is enhancing the fun!

Here’s how it works: when the player obtains a Claw bonus, they can either keep it to moderately upgrade their firepower, or burst the claws to accelerate their orbital speed and maximize damage output. The catch? This acceleration only lasts 15 seconds.

But here’s the trick: if the player grabs another Claw bonus while bursting, they can chain the acceleration indefinitely, overwhelming enemies with nonstop firepower.

So… can you handle the Thunder Claws? Or will you lose trying? 😈

Looking ahead, the multi-directional scrolling level is still planned — just not yet. And for version 5.5, I plan to bring back two revamped levels from version 4…  Or maybe add a top down level like in  Thunder Force II?  Time will tell :).

Nice Environment !
I had already buy a halloween bundle 2 years ago with many of your Warped assets.
My problem is that this lava level is not inside. I would like to buy it apart  of the rest of the warped collection since already have almost everything (I suppose). Is it possible ?

Hello Ansimuz !

I have a request, there is this level in your Warped Collection :
https://ansimuz.itch.io/ultimate-warped-collection/devlog/863388/mega-bot-lava-a...

I had already buy a halloween bundle 2 years ago with many of your Warped assets.
My problem is that the lava level is not inside. I would like to buy it apart  of the rest of the warped collection since already have almost everything (I suppose). Is it possible ?

Another question, do you do custom missions? I need an original Thunder Force-style ship sprite. If so, what are your rates please?

Update 4.3

Here’s the link to play it: https://triganov.itch.io/thunder-force-heaven

Hi !

In order to be patient while waiting for version 5, this update is all about refining the current experience and making the game smoother, fairer, and—let’s be honest—more fun.

Here’s what’s new in 4.3:

• Game is now playable with Keyboard or GamePad
  
• Difficulty Rework (Levels 1-5)
  I ran a bunch of playtests and decided to tone things down a bit. The early game should now feel less punishing and more enjoyable, especially for new players.
• Slower Enemy Bullets.  Enemy projectiles now move at a more manageable speed. Still dangerous, but way less unfair.
• Persistent Progression. Lives, score, and weapons now carry over from one level to the next. It adds a stronger sense of continuity and reward as the player move forward.
• More Bonuses = More Fun. The player will find more bonuses scattered throughout the game now. It feels more generous ;)

These tweaks might seem small on paper, but together they make a big difference in how the game feels. It's all about making Thunder Force Heaven more accessible while keeping the thrill intact.

As always, if you want to share feedback, do not hesitate :).

The best is still to come—Version 5.0 is cooking and it’s gonna be wild. 🔥

Hi Ansimuz!

I purchased quite a few of your assets to create a Thunder Force FanGame. I find that your creations really capture the 16-bit era of consoles, which is exactly what I needed.

I used assets from Warped, as well as Gothic Vania and Legacy.

My game has 4 levels and 3 bosses, and it would be a pleasure if you could play it or take a look:

The game is currently at version 4.1 and is playable on Itch.io: https://triganov.itch.io/thunder-force-heaven (Sometimes, on the first launch, the Enter key might not respond on the title screen. Just press Control + F5 to refresh the browser and it should work. Don’t ask me why—this issue only appears on the Itch.io platform.)

And here’s the link to the Let's Play video: https://www.youtube.com/watch?v=uaIhP5uIqnk

Update 4.1

Here’s the link to play it: https://triganov.itch.io/thunder-force-heaven

The upcoming Version 5.0 I’m planning to release is very ambitious because it will introduce a top-down level (in the style of Thunder Force II). It will also include another new level with completely free-movement gameplay. 
But before adding new features, I felt it was important to consolidate what already exists. And it definitely needed it.

This Version 4.1 focuses mainly on improving the backgrounds and cutscenes. I think the story I’m telling through my game is interesting (yes, I like to give myself some credit from time to time). However, cutscenes were seriously lacking life—they just showed characters talking to each other.

Plus, the backgrounds in the levels also felt static and missed a sense of animation.

Here’s a list of the most significant changes:

1. The font

The most important change is updating the font. The old font, Aldo The Apache, was very stylish—it reminded me of the fonts used in arcade machines. However, it only displayed uppercase letters, which made reading difficult—especially since my game features dialogues that can last several minutes.

The old version

The new version. Easier to read, isn't it :) ?

2. New background for the city of Slyana

Ansimuz released an updated version of their asset, Cyberpunk-Street-Files. This new version fits perfectly with the vibe of the capital city of the planet Slyana. And since I’ve mastered animated backgrounds since Version 3.5, I decided to animate Slyana’s cityscape by triggering a blackout right after a bombing. I think it adds a nice touch.

This old background was already great...

...but this version rocks so much !!

3. Add a Spaceport

Previously, we only saw the player’s ship approaching Slyana and requesting access from the planet’s AI. Now, there’s a proper spaceport serving as the location for handling the landing procedure.

Nothing in background, juste the player ship and the planet...

Now, there is a big spaceport :)

4. The cave in Level 1

I’ve added a dimming effect as you progress deeper into the cave. This adds some tension as the boss arrives, leaving you in near-total darkness (though you can definitely hear the boss approaching!).

5. More battle in high Slyana 

In the cutscenes after Slyana’s city, we learn that the high-business district was placed under quarantine to organize betting fights. In these deadly games, Slyana’s upper-class citizens fight to the death, pledging loyalty to the Emperor they’re willing to die for. To reflect this atmosphere in the cutscene, I’ve added background elements like ships battling each other during the dialogues.

And, of course, there are a lot of fixes with this version ^^.

When the next big Update (5.0) ?

I don’t think I’ll release a new version before the 5.0 update. But then again, never say never.

As a reminder, here are the new features I plan to include in Version 5.0:

• Since FireLeo2 is used in Lelighter's campaign, I’ll add a top-down level (similar to Thunder Force II).
• The UI will adapt depending on the selected campaign, reflecting the specific ship being controlled. This is to pay homage to each of the three Thunder Force episodes.
• Levels 1 and 2, along with their associated cutscenes, are currently in 320x200 resolution. I’ll upgrade them to 640x400 (this might take some time).
• Add a new level to Marshall Triganov's campaign: Planet Amond.
• Include additional cutscenes to further narrate the unfolding adventures. 

Big Update: Version 4.0

Here’s the link to play it: https://triganov.itch.io/thunder-force-heaven

Here it is, at last: Version 4.0 of my Fan Game inspired by my favorite game!

As promised, this new version introduces a brand-new campaign featuring Marshall Triganov.

Marshall Triganov is a key character in the game, and for his campaign, I've enhanced both the gameplay and the game engine.

Introducing the new "Claws" gameplay mechanic This feature is a special treat for fans of Thunder Force II, III, and IV. With the Claws:

1/Two mini satellites orbit around the Rynex, firing additional missiles similar to the weapon selected by the player.

2 very usefull satellites for destroy ennemies above and below

2/The environment evolves dynamically.  Now, in the level 1 of Triganov campain, the background evolves from day to night, from clear skies to rain, and even features a city being destroyed right before the boss battle.  This allows better immersion of the player in the universe that I want to show

Background evolves from day to night

3/Enemy patterns are more complex. One example is a mech that shoots, then jumps off a flagship, follows the player's vertical trajectory, and charges at them while firing a massive laser.

The newly added level is the longest level in my game, lasting about 3 minutes and unfolding in three distinct phases: in the air, underground, and finally, the boss battle.

It's Boss Time !!

When will the next update be released?

For Version 5, you'll have to wait a little while. But rest assured, this new version will be just as ambitious as ever.

I’d like each of the three campaigns to feature a unique ship for the player to control:

• Dr. Lelighter pilots the FireLeo2 (Thunder Force II)
• Marshall Triganov pilots the FireLeo3 (Thunder Force III)
• General Victory pilots the FireLeo4 (Thunder Force IV)

Planned updates:

• Since FireLeo2 is used in Lelighter's campaign, I’ll add a top-down level (similar to Thunder Force II).
• The UI will adapt depending on the selected campaign, reflecting the specific ship being controlled. This is to pay homage to each of the three Thunder Force episodes.
• Levels 1 and 2, along with their associated cutscenes, are currently in 320x200 resolution. I’ll upgrade them to 640x400 (this might take some time).
• Add a new level to Marshall Triganov's campaign: Planet Amond.
• Include additional cutscenes to further narrate the unfolding adventures. 

Big Update: Version 3.5

 Here’s the link to play it: https://triganov.itch.io/thunder-force-heaven

Yes, I know, I promised you Version 4 of my game. But since this Version 3.5 concludes the first campaign of my game, I had to share this new update with you.

For your information, the final version of my game will include three campaigns: 

• The campaign of Dr. Lelighter (which is now complete)
• The campaign of Marshall Triganov (currently in development)
• The campaign of General Victoria (not started yet)

Let’s dive into the details of what’s new in this version.

What's new in this update ?

A brand-new boss with multiple parts

 Until now, the game only had two bosses:

• The first boss was vulnerable everywhere and consisted of just one part.
• The second boss was a bit more complex in terms of code, as it had a vulnerable part (its head) while the rest of its body was invulnerable.

This third boss not only has vulnerable and invulnerable parts but is also made up of multiple sections. This means the player must destroy each of these parts to defeat it.

It’s a heavy warship you’ll have to face. Will you be able to overcome it? :)

2 new cutscenes

 These new scenes precede and follow the boss battle I just described. As I mentioned earlier, the final scene concludes the story of Dr. Lelighter.

In short, during the boss battle, Slyana is in the midst of a civil war. One of the four sons of the late Empress sees a strange opportunity in this chaos: He puts an entire city under quarantine so the planet’s elite can freely bet on the outcomes of the battles taking place there. (This might remind you of Running Man with Schwarzenegger!)

Credits Page (Available in Menu Interface)

I’ve also added a Credits page to honor my work and give recognition to all the creators of the graphic elements I’ve used.

Thank you guys for all you great creations that helps me in my adventure :)

Name of characters in the DialogBox 

Finaly, I’ve added the names of the characters above the dialogue bubbles during the cutscenes.

As you can see on the screenshot above, The name of the caracter is displayed just above the dialog box

Oh and maybe you noticed it but in the screenshot above, you can observe that the player does not control R-Type ship anymore. It's FireLeo2 from ThunderForce II :).

When is the next big update 

I’m planning to release a major update (Version 4) before the end of the month. 

This Version 4 will include: 

• 1 additional playable levels which introduce Triganov's campaign
• 2 new cinematic scenes
• Adding the Claws gameplay mechanic. In Thunder Force IV, there’s a Claws power-up that allows two small satellites to orbit your ship, adding extra firepower.
• And lots of other updates, fixes, etc.

Medium Update: Version 3.1 of my Prototype is now available! Here’s the link to play it: https://triganov.itch.io/thunder-force-heaven

What’s new in this update?

3 new cutscenes 

 In the previous version, there were only two scenes that didn’t really explain why there’s a galactic war. I’ve added 3 new scenes to give more background to the universe I’m creating.

Why add cutscenes? Isn’t the point of a sidescroller just to blow everything up without thinking? Yeah… But when I was a kid, I used to really enjoy playing Thunder Force IV. Even though I was convinced there was a grand story behind the game, the game itself didn’t really show it. It’s only when you finish the game that you get an explanation of the incredible feat you just achieved.

Many Planets, many different cultures 

Fixes for several annoying bugs 

• The most important one for me is the fix for a bug that prevented me from applying a fade-out effect to the music before a boss fight. This is crucial because it amplifies the tension when the music stops, and everything goes quiet just before the appearance of a terrifying boss. 
• Improved dialogue boxes: When no character is speaking in a cutscene, there’s no longer a large black rectangle awkwardly displaying dialogue boxes. 
• And many other small bugs have been fixed! :)

When is the next big update 

I’m planning to release a major update (Version 4) before the end of the month. 

This Version 4 will include: 

• 2 additional playable levels (one of which features a boss)
• 3 new cinematic scenes
• Replacing the R-Type ship with the Fire Leo 2 from Thunder Force 2 
• And lots of other updates, fixes, etc.

Hello there !

I’m Triganov. I’m a professional backend developer. In my free time, I’m passionate about developing retro 2D video games.

I mainly develop in JavaScript and C#.

Right now, I’ve given myself a month and a half off from work to focus on my game and truly feel like a real video game developer. Why, you ask? Besides the fact that I enjoy creating video games, there’s also the lingering memory of being told as a teenager that I’d never be able to develop a video game... Let’s see if I can silence that demon from the past. ^^

Strengths:

• I’m pretty skilled at debugging.
• I have solid knowledge of TechnoSoft games.

Weaknesses:

• I struggle to create my own sprite sheets.

Thunder Force Heaven

Last Update: Version 3 of my prototype is now playable !

Here is the link to play it : https://triganov.itch.io/thunder-force-heaven

What's new in this update ?

Translation

The first thing I updated in my game was the translation. All the text was originally in French. But the rule is: if anyone in the world might be interested in the Thunder Force story I want to tell, I need to translate my scenario into the most widely spoken language.

Texts are now translated in english

Diagonal Collision

After that, I was stuck on a very tricky issue: diagonal collisions. Of course, I asked ChatGPT for guidance, but every time I tried to implement it, I got discouraged by the math involved (vector projections). During my vacation, however, I had a 4-hour jet lag (in the wrong direction). One night, I finally decided to sit down and study vectors. It was 4 a.m. when I finally got it working. Lord... it’s no big deal in hindsight, but I was so proud of myself!

Diagonal collisions are now handled 

Improve Level Design and Ennemy pattern

Third, the time had come to improve the level design for the 3 existing levels. Sure, I still need help from a level designer, but now the execution of the levels is decent. Each level now features at least 4 different enemies (not counting the boss)

If this scene, 3 ennemies with very specific fire and movement patterns

If you take a look at the screenshot above for example. You will find :

-Two tanks. Theses tanks go simply from left to right or right to left but the fire pattern is quite interesting : I added a raycasting mechanic that allows tanks to fire only when the player’s ship crosses the red line.

-Two Spaceship. For the enemy ships in the upper left corner of the screen, they initially move from left to right or right to left, but they also try to get as close to the player's height as possible. In the second phase, they perform a small up-and-down maneuver during which they fire multiple missiles. After that, they accelerate and exit the screen.

-Many spikes. Finally, there’s an enemy I call the TechnoLizard. In the screenshot, it has just exploded (you can see the spikes in the bottom right scattering in all directions). The TechnoLizard is dropped by ships that speed across the upper part of the playable area. Once deployed, it moves along the ground, trying to get as close to the player as possible on the X-axis. Then, it explodes, releasing a barrage of spikes.

Dangerous Events

Finally, saving the best for last—I’ve added event-based elements to the levels. At certain points during the game, a visible event in the background can occur (for example, a volcano erupting or, as you can see in the screenshot below, a missile being launched from the enemy’s base).

They are very tiny, but there are 3 missiles launched in the background in the sky

When an event like this happens, the UI displays messages and plays a “DANGER, DANGER” alert sound to warn that a threat is coming from above. I think it’s pretty cool because it encourages the player to pay more attention to what’s happening in the background.

And for the next Update ?

For the next update, I don’t want to add the 4th level just yet. There are several things I need to do first:

• Add cutscenes for Level 2
• Create a mini-level for both Levels 1 and 2 (necessary for the story progression)
• Design the boss for Level 3
• Add cutscenes for Level 3

I'm posting this here to share the latest updates on my project and, who knows, maybe get some help from a Level Designer or a Design Artist. For now, this project’s main goal is to revive a franchise I truly enjoy: Thunder Force.

Here is the link to play the game :
https://triganov.itch.io/thunder-force-heaven

Since I was a kid, I've been a huge fan of the Thunder Force series. I started with what many consider the best in the series: Thunder Force IV. The soundtrack, the monster designs, and the various planets we visit made me want to learn more about this universe. .. Good news : The series has actually a rich universe and coherent storyline.

That's why I set out to develop a Thunder Force fan game: Thunder Force Heaven (notice the play on words when pronounced – Thunder Force Heaven = Thunder Force Seven :)).

So far, I've created three small levels. I relied on assets from Animuz (who, by the way, is excellent at mastering the Genesis design style).

Below, you can see some Screeshots of my project : 

Level 1, Planet Mystic. The planet where we discover that our ship is an exact replica of an ancient alien vessel that once fought against a mysterious empire known as the "ORN Empire."

Level 2, Planet Cosma. On a planet located on the outer edge of the galaxy, we want to meet Triganov, an old Mystic Marshal who has exiled himself to this remote world.

Level 3, Planet Slyana. We return to our own planet, where, following the death of the empress, a bloody fratricidal war is raging between her three children.

Level 4, Planet Amond. A planet where all those sentenced to death and enemies of the empire were sent.
Coming soon

Thank you :)