There are a lot of horror movies that have an unstoppable monster as its lead. It Follows, Halloween, The Babadook, etc. In these movies the monsters are terrifying because no matter what you do, you can’t stop them forever. You have to be a little careful about using this technique in games. Like a jumpscare, after about the third encounter you become desensitized. Sure, it’s imposing and will kill you if you don’t do anything about it… but you’ve also survived this a few times already. The key to making an unstoppable antagonist be effective is to use them to punctuate the game instead of being the focus. Use them as a design tool to get the desired effect without breaking player immersion.

Narrative Payoff

This is perhaps the most common use of an unstoppable enemy. Players are first warned about the enemy in the narrative before running into them at a random time during their playthrough. This foreshadowing communicates to the player that this is not a normal enemy and will not be defeated in a conventional way. The unstoppable enemy often interacts with the player throughout the game, creating an antagonistic relationship and building them up as the “big bad”. Overcoming this monster is a great way to tie up the story and give your players a sense of accomplishment, the game isn’t just over, they’ve overcome the impossible! Which still feels great even if you know it’s coming.

Narrative Payoff Example: Alien

We talked about Alien: Isolation in our podcast, and in a previous post about dread in games, but just like in the movie, it just keeps coming back. In Alien: Isolation the Xenomorph is an unstoppable force that must be survived, not killed. You’ll encounter the Alien several times in your play through, often serving to punctuate your mistakes when solving other parts of the game. Made too much noise trying to defeat androids? Felt over confident and doubled back to grab that spare part? Too bad, you’ll be seeing the Xenomorph soon. All of this makes finally defeating the Alien at the end that much more satisfying.

Themed Guide

An unstoppable enemy can be a great way to force players into a specific area in the game where the next act can begin. We’ve talked about using keys before, but using an enemy that can’t be killed is a lot scarier than a locked door. The designer has complete control over where the player will need to run in order to survive, without needing to tell the player what to do or take them out of the immersion at all. They feel completely in control of their actions… while still going exactly where you want and running for their life.

For example, let’s say your player encounters the monster in a hallway and it starts chasing them. The player, knowing they can’t kill it, will be forced to run in the other direction. All according to your plan! You get to direct how the encounter will play out. You can lock them in a specific area, hide loading time by forcing them to take an elevator, or force them to backtrack through a section they may not have otherwise revisited.

Themed Guide Example: Nemesis

In Resident Evil 3: Nemesis, you, as Jill Valentine, are relentlessly pursued by Nemesis, a former human mutated by the Umbrella corporation into an unstoppable monster. Taking inspiration for the T-1000 from Terminator, Nemesis relentlessly pursues the player throughout the story. Under the hood, the monster is used as a transitional device where players are given the option to fight or run away. Your choice changes the game going forward; the items you pick up are affected, and even the narrative scenes you see change. The designers only trigger a Nemesis encounter after a certain set of conditions have been met (progress, area of the map, etc.). This allows the encounter to make sense with the current narrative and move you to the next relevant part of the story. After making it to the police station players are not allowed to leave before completing the area because Nemesis is waiting outside.

Built-in Timer

Good monsters are usually metaphors. Likewise, an unstoppable enemy can be a stand-in for something that feels inevitable. Something to survive or fight against as long as possible. Which is why this kind of monster makes for the perfect hidden clock or timer. While a ticking time bomb count down in the corner of the screen is always fun, sometimes you don’t want a literal clock. You can still give the player a limited amount of time to accomplish a task without showing them the actual time by using an unstoppable enemy that will end the game if they aren’t fast enough. Or in the opposite direction, let them reach for their high score in survival time without showing a stopwatch. Can they keep the zombie hoard away long enough?

Built-in Timer Example: Moon

For some reason there are countless pieces of media where humans deface or destroy the moon. It’s possible that that’s a normal human reaction to something so massive and capable of destroying all life on earth. Which is why it’s the perfect example of a timer hidden as an unstoppable enemy in The Legend of Zelda Majora’s Mask. In Majora’s Mask, you have just three days before the moon crashes into Terminus and destroys everyone. The game’s three-day cycle is roughly 54 minutes long in real-time. You can’t destroy the moon, and when that timer is up it’s game over. The player sees the timer constantly looming overhead, without needing a flashing countdown to scare them. The creepy face is way worse anyway.

Mix Them Together

Sometimes a good unstoppable enemy is a mix of a few hidden design tools. In Metroid Fusion, the X Parasite is an alien clone of the player’s character, Samus. The X Parasite seeks out the apex predator of the world it lives in, mimicking them in an effort to survive and thrive. As a result, the X Parasite has all of the player’s attacks and is at the same, or higher power level. Unstoppable.

Throughout the game you interact with the X Parasite at random times, forcing you to hide or retreat. Players are in the position of prey being hunted with no other choice but to run. If you know that the X Parasite is in a certain area of the map you better avoid it, or find a different route. The X Parasite is a clever mix of a Themed Guide, routing you to different areas while filling you with dread and building you up for the big Narrative Payoff.

Like a lot of great horror movies with unstoppable monsters, the most important aspect is the protagonist’s response to the monster NOT the monster itself. An unstoppable monster can get boring. To use them effectively, get creative. Use your monster as a design tool to make the player’s experience more memorable.