Many game fans have enjoyed the Tetris movie, which chronicled the creation and licensing of Tetris, the addictive game that Alexey Pajitnov created behind the Iron Curtain. His friend Henk Rogers went through a great deal of trouble to license the game in Russia and even get Pajitnov out of the Soviet Union decades ago.

But there’s one more chapter to the tale unfolding.

Today, Pajitnov and others who unearthed a forgotten game in the Tetris canon talked at the Game Developers Conference about Tetris Reversed, a prototype for a game that was considered lost.

But little did Pajitnov know that an engineer in charge of the game, Vedran Klanac, had kept a copy of it. Through the help of intermediaries, he showed it to Pajitnov and the two shared their memories of what happened to the lost game.

Pajitnov, originally from Moscow, became famous as a computer engineer and inventor of the legendary computer game Tetris, which he created in the 1980s while working for the Soviet Academy of Sciences. Rogers got the rights to the game and eventually got Pajitnov out of the country. They retold some of this story at our GamesBeat Next 2023 event last October. (Be sure to sign up for GamesBeat Summit 2024 on May 20-21; you can use a 25% discount code: gbs24dean25.

Pajitnov has lived in the U.S. since 1991, where he has been involved in the development of games such as Pandora’s Box and worked with companies such as Microsoft and WildSnake Software. In addition to his iconic Tetris game, he is behind titles such as Hatris, El-Fish, and Hexic among many others that have deepened and expanded game design. He was awarded First Penguin Award at Game Developers Choice Awards in 2007 for his breakthrough in the world of games. And his story was the subject of the Tetris movie.

Klanac is the CEO of Ocean Media, and he is originally from Zagreb, Croatia. He was an aerospace engineer who started his career in the games industry with Croteam where he built the physics engine for Serious Sam 2.

Since 2006, he has been running Ocean Media, a game publishing company with a focus on consoles. During the last 20 years, he was involved in production as a programmer and executive producer in more than 200 projects. And it turns out he was the programmer who created the Tetris Reversed code based on instructions from Pajitnov, who had passed them on through a middleman.

More than a decade ago

In 2011, programmer Vedran Klanac went to the NLGD Festival of Games in Utrecht, The Netherlands. He listened to a talk on a charitable effort from Martin de Ronde, a cofounder of game studio Guerrilla Games. Klanac said in an interview with GamesBeat that he listened to De Ronde’s talk and offered to help. De Ronde came back months later saying he had an agreement with Pajitnov about creating a new prototype for a Tetris game.

De Ronde asked if Klanac if he wanted to make Tetris Reversed by Pajitnov.

“Are you kidding me?” Klanac reacted.

They started the project. De Ronde served the go-between on the project, mediating between designer Pajitnov and engineer Klanac. De Ronde wanted to create a title for OneBigGame and donate most of the proceeds to charity. It was a side project that was separate from Guerrilla Games, and he wanted the games to come from famous game developers like Pajitnov.

“We discussed this recently but I never knew who Vedran was during the project,” Pajitnov said during the panel. “Most of the players all concentrate just on the profile in the game. All that matters is the profile of the garbabe in the playfield. The placement of the specific pieces in Tetris. If you remember similar board game, the player tries to use all of the space. I thought maybe this could be done, to attempt to use all of the playfield. I found a way to do it by reversing the game. Instead of putting the pieces in the playfield, I used them to eat the items in the game. That was the main concept of the game.”

De Ronde would receive instructions from Pajitnov about the design of the game, and then pass them on to Klanac, who would turn around and code the game. Then he would pass a note back through Pajitnov about what had been completed. It took a month to do the first prototype.

“I had some questions about how it should work. And then we started the iterations which the communication group” undertook, Pajitnov said.

They did most of the work from March 2012 to November 2012. Klanac did the work in his own game engine, on his own time. And, fortunately, he had a good archiving system.

Notes would be passed back and forth, and Pajitnov never actually met Klanac. And it was just a side hustle for Klanac. Pajitnov said he remembers the prototype and he played it lot.

“Martin was in the middle. And this is one of the reasons why Alexei actually never communicated with Klanac,” he said.

“Then we started doing iterations on how to create the first version,” Klanac said.

As the fall approached, Klanac said everyone was busy. de Ronde was in the process of selling his studio, Guerrilla Games, to Sony. Then the project slowed down and de Ronde said it was dead in the water. Communication became more sporadic.

Three years later, Klanac emailed De Ronde about what was the status of the program.

“Is this dead in the water?” Klanac asked.

De Ronde had no answer but thought it was likely canceled. Then the game sat fallow. Klanac tried one more time to get clarity a year later. But de Ronde never responded to that message.

A playable prototype

So Klanac stopped working on the project and moved on. But he knew the prototype was complete and it could be played.

And so it was lost.

Tetris Reverse unearthed

Vlad Micu, a business development professional, unearthed this story and united Pajitnov and Klanac for the first time. Micu had met Klanac in Taipei in 2017. They had been friends for a while and saw each other annually at the Reboot Develop Blue conference in Dubrovnik. They had dinner there in April 2023 along with Kate Edwards, CEO of Geogrify, and I was there too. They were talking about the Tetris movie.

Then Klanac mentioned that he still had the prototype of a game called Tetris Reversed in his personal archives. He shared the backstory with Micu, who was stunned that there was a lost prototype of a Tetris game that was never published. And he was also surprised that Klanac and Pajitnov had never met in person.

“Vedran, out of nowhere, drops this massive bomb on us,” Micu said.

Micu was working on a game conference in Prague and managed to get Pajitnov to come out and give a talk.

“I actually ended up sitting down with Alexei and bringing all of this up to him,” he said.

Micu told Klanac he should consider doing a talk about it at the GDC, and they agreed it would be a good story as a kind of post-mortem for a game that had just a prototype. Through Edwards, Micu got in touch with Pajitnov in person and he had gotten the GDC staff’s attention with regards to the story about the lost game. The Tetris company had no objection to the session.

The GDC approved the session out of the interest of the preservation of games. And the story was retold today in a panel at the Game Developers Conference. For the first time in public, they showed the video of the prototype in action.

Pajitnov went over the design decisions, the iterations and the development process. It’s not clear yet if the game will ever be officially published.

“When you see the gameplay video, and when you look at the design elements. This is Tetris for like 300 IQ people,” Pajitnov said.

How the game works

Concept

This game idea started from the original game of Tetris. Klanac analyzed the game and noticed that the profile of the playfield content is the main point of care of the player. Somehow the main strategy of a regular player in Tetris is to build and maintain the appropriate profile of the “garbage” –without bumps and with deep narrow holes of certain configurations.

If you played Pentomino or any other board variations, you’ll notice that the playing happens all over the playfield – you try to find appropriate spot for the piece everywhere on the playing field. So Klanac tried to understand how to make all the space available.

Game dynamics

Generally, it is borrowed from the original game – the tetramino piece falls down, the player controls its position (to left or to right), state (rotate 90 degrees, maybe replace it, if the “hold”-option is on), and movement (acceleration – “soft drop”, maybe even some “move-up” or pause options,  if the game is too hard to play).

But the main new feature is to make the entire playfield accessible, Klanac said. That was the main point of the new game design. He took the next piece and made it fall down on the front of the playfield full of garbage. At a certain position, Klanac wanted the piece to be embedded into the playfield – with certain UI action. The piece would be placed (or attempted to be placed) – so, its “life cycle” is to be over and the next piece is to be generated. That’s why UI action must be something like a “hard drop” from the original game, Klanac said.

This way the main game dynamics is pretty much set up.

Rules

Most of the rules are about the “embedment” action. If all the cells under the piece are full (grey-colored) – then the placement takes place and these cells are cleared. Otherwise, the move fails. In the real prototype, Klanac believed, four background cells remained untouched, the piece disappeared and then the entire playfield got “reversed”: all the no-empty cells turned empty and empty cells – no-empty. Now, Klanac changed this rule a bit, but historically that is what has been implemented.

Later this “Reverse” procedure was implemented in a prototype as a separate action that the player can perform with a certain button anytime during the move. The reason for that was to let the player keep playing if he “ate” almost all the garbage and there is no area for the piece placement.  The number of these “Reverse” actions was assigned limited – 15 or 20. After they are exhausted, the “Game over” happens.

The extra rule was about the collapse of the empty lines. There was no need for this feature, but the great emotional effect made Klanac really want it in a new version. The collapse rule is very simple – if the line of garbage is cleared,  then it collapses as in the original game. The only question is about the liberated space on top of the playing field. He decided to make it completely unplayable afterward. No placement is allowed there and no reversing of the cells. So, the collapse of the line literally shrinks the playing field, showing real progress in the gameplay and making a game harder and harder. Klanac thinks it was a very good decision.

Klanac said it is called Tetris Reverse because it introduces a reversing mechanic where there are two conditions. You can reverse the board, which literally means inverse, or reversing light and dark cells.

That is, the board flips so that the area where a block can flow down in the open-air space becomes an obstacle, and the former obstacles become open spaces on the board.

On the right side of the screen, you see the number of reverses that you’re still left with and how many times you can still reverse. If a piece falls from the top all the way down to the bottom and you don’t place that block, then it will automatically reverse the game.

The idea is to survive as long as you can.

Pajitnov remembered working with de Ronde, asking him to re-create the prototype that Pajitnov had created. Klanac, through de Ronde, promised to work on two versions of the prototype. Then the project just stopped going forward.

“I had almost completely forgotten about its existence,” Pajitnov said.

Now he wonders if the game can be published as it is today.

“Basically, it’s another version of Tetris,” said Pajitnov.

Pajitnov said he was glad the prototype will be preserved for history. As for the current nostalgia around Tetris, he said it’s nice that Tetris is still alive.

“I’m sure there is going to be enormous interest as there is a new prototype that people don’t know anything about,” Pajitnov said.