Echo: The Future of Video Game AI

Echo is a stealth, survival, puzzler game which is available on Steam, GOG, and PS4. Coming from Danish Development Studio Ultra Ultra and having several ex-Hitman staff working on the project, it is everything you would come to expect from both an indie game and a triple-A stealth title. You play as En, a woman who has just come out of 100 years in stasis and is set on finding a “Palace” with the power to resurrect her dead friend. Once inside, you begin to encounter grotesque copies of yourself and must try to discover the secrets of this planet-wide structure (which, impressively, isn’t procedurally generated). Echo is extremely rooted in the stealth gameplay which the crew is so well-known for, and combines this with key components of the survival-horror genre. Energy management is an integral part of the game, forcing the player to weigh up the pros and cons of, say, jumping off of a ledge to get to a lower level, versus dispatching the pursuing enemies with a shot from their gun.

What makes this game so unique is the way it handles enemy AI. The foes you will end up facing in this game are referred to as “Echoes”, copies of the player created by the Palace, who can learn from the player and mimic player actions. If you play in a very gung-ho fashion, shooting any enemies you come across and sprinting through the levels—a style of play I wouldn’t personally recommend—you will find yourself facing several enemies with increased speed and the ability to shoot at you. Should you alternatively play stealthily, crouch-walking everywhere and using stealth takedowns to dispatch opponents, your enemies will, in turn, become stealthier and will now have the ability to stealth takedown you. You really are your own worst enemy when it comes to Echo; in-the-moment choices can now cause a significant issue for you in the next cycle. Yes, you read that right: cycle. This game works on a cyclical light and dark phase. When the lights are on, the Palace can record any actions you perform, using them in the next phase as instructions for how the Echoes will behave. When the Palace has logged enough actions, it will enter a dark phase where all power is shut off. These are some of the most freeing sections of the game, where you can act without any future repercussions. This cyclical style of gaming has lead to some very interesting scenarios, such as gun-toting enemies who can’t open doors, or grape-eating Echoes who crouch-walk everywhere. The number of actions that can be mimicked by the Echoes seems limitless, with any action performed by the player potentially being an action that can be recreated by the enemy. This system can become almost humbling as you watch an Echo snatch a key you needed to progress further, or sneak up behind you and perform a stealth takedown (embarrassing, I know).

Echo isn’t the first game to try and use AI to improve the feel of gameplay. 2014’s Alien: Isolation is a game which proclaimed all throughout its marketing to have truly unpredictable AI. The Xenomorph would move around seemingly at random, but always in the general vicinity of the player. Earlier this year, the developers behind Alien: Isolation revealed how this system worked. It was achieved by using a two-brain system involving both a Director brain and the Alien’s brain. The Director brain always knows where the player is at any given time, and calculates how tense the player is via how close the player is to the Alien and other factors, like if the player could see the creature directly and how much or how little progress the player is making. The Alien functions on its own set of rules, however, with it searching for audio-visual cues to the player’s location, whilst also being given hints from the Director. As you perform actions in front of the Alien, it will unlock more sub-options within the “brain”, so that it appears to learn from its experiences with you. For example, if you hide a lot in lockers, the Alien will be more likely to check lockers. Looking back, Alien: Isolation wasn’t even the first game to use this Director brain system, with it existing as far back as Left 4 Dead and Halo 2. These systems control the tension of the players, singling out those who wander off and allowing players to control the tide of battle with the elimination of larger enemies making the smaller foes retreat.

With Echo comes the realisation that we do not want “true” AI in video games, because an artificially intelligent NPC would arguably have the same goal as a human player: to win. Echo, and Alien: Isolation before it, have proven that the best way to create an immersive gaming experience is to create scenarios where it feels like your opponents are adapting to your strategies, moulding their tactics to your unique playing style and forcing you to evolve as a player. It is clear to me that the direction video game-AI is taking isn’t simply to make NPCs more “realistic”, but to allow the player to tailor a custom experience for themselves without even realising they are doing it. Echo is almost a proof-of-concept for what’s to come, an amazing game on its own merits that I would 100% recommend everyone plays. This title not only looks stunning and has a perfectly integrated soundtrack and HUD system, but challenged the stagnant gamer I have become over a lifetime of gaming.