Difficulty
Difficulty increases enemy HP, movement speed, attack damage, and most importantly spawn pressure. This makes it an essential stat for high-kill runs, as higher Difficulty results in more enemies being available to kill over time.
For the final swarms, there are specific percentages to target to maximize your kills but for non-swarms they are significantly higher.
The maximum number of ghosts alive is:
- 400 ghosts before the 2-minute mark
- 300 ghosts after the 2-minute mark
How many ghosts should spawn per "wave" is in part decided by your difficulty percentage. To maximize your kills during a final swarm you need at minimum the following difficulty percentage at given stages/time stamps. The game differentiates between the ghosts spawned before the 2 minute mark and those spawned after:
The Graveyard always uses the Stage 1 difficulty scaling, no matter where the ghosts spawn on the map.
After completing Stage 3 and teleporting to the final boss area, the game still treats this as Stage 3 internally. This means the same difficulty thresholds shown for Stage 3 continue to apply during the final swarm after killing the final boss.
The spawn system is reactive to how many enemies are currently alive. If you clear enemies fast, the game continuously replaces them at a quicker rate than if you aren't able to kill them, resulting in much higher overall spawn pressure. For example on Stage 1 at 200% Difficulty over 1 minute and 30 seconds (of the start of the game):
- If you instantly kill every enemy that spawns → ~275 enemies will have spawned
- If you kill nothing at all → only ~89 enemies will have spawned in the same time
Other notes for the difficulty during non-swarm:
- A maximum of 550 enemies can be alive at the same time. If this limit is reached, no new enemies will spawn until some are killed.
- There also seems to be a upper spawn rate limit of roughly 500 enemies per second, even outside of swarms. However, reaching this would require an absurd amount of Difficulty. Testing at ~20,000% Difficulty did not hit this limit, so in normal gameplay this cap is effectively unreachable. This means that more difficulty will always increase the spawn pressure outside of final swarms assuming you can actually kill those enemies. Technically there is an upper limit, but I was unable to verify what percentage would be required for that. It doesn't really matter either since it's well above 10k% difficulty which you will never reach in normal gameplay anyway.
For the final swarms, there are specific percentages to target to maximize your kills but for non-swarms they are significantly higher.
Final Swarm
During the final swarms there is a maximum number of ghosts that can be alive at the same time. If that many are alive at the same time, no more ghosts will spawn until one is killed.The maximum number of ghosts alive is:
- 400 ghosts before the 2-minute mark
- 300 ghosts after the 2-minute mark
How many ghosts should spawn per "wave" is in part decided by your difficulty percentage. To maximize your kills during a final swarm you need at minimum the following difficulty percentage at given stages/time stamps. The game differentiates between the ghosts spawned before the 2 minute mark and those spawned after:
Having more difficulty than these percentages at those given points of the final swarm will not increase the spawn rate further, only their other stats. It is somewhat counter intuitive that earlier stages require higher Difficulty to reach the maximum spawn rate. But it is indeed how it works. After the 2-minute mark, the required Difficulty is always lower.
The Graveyard always uses the Stage 1 difficulty scaling, no matter where the ghosts spawn on the map.
After completing Stage 3 and teleporting to the final boss area, the game still treats this as Stage 3 internally. This means the same difficulty thresholds shown for Stage 3 continue to apply during the final swarm after killing the final boss.
Normal stages (non-swarms)
Outside of swarms, increasing Difficulty will almost always increase the amount of enemies the game tries to spawn (as long as you are able to kill the enemies).The spawn system is reactive to how many enemies are currently alive. If you clear enemies fast, the game continuously replaces them at a quicker rate than if you aren't able to kill them, resulting in much higher overall spawn pressure. For example on Stage 1 at 200% Difficulty over 1 minute and 30 seconds (of the start of the game):
- If you instantly kill every enemy that spawns → ~275 enemies will have spawned
- If you kill nothing at all → only ~89 enemies will have spawned in the same time
Other notes for the difficulty during non-swarm:
- A maximum of 550 enemies can be alive at the same time. If this limit is reached, no new enemies will spawn until some are killed.
- There also seems to be a upper spawn rate limit of roughly 500 enemies per second, even outside of swarms. However, reaching this would require an absurd amount of Difficulty. Testing at ~20,000% Difficulty did not hit this limit, so in normal gameplay this cap is effectively unreachable. This means that more difficulty will always increase the spawn pressure outside of final swarms assuming you can actually kill those enemies. Technically there is an upper limit, but I was unable to verify what percentage would be required for that. It doesn't really matter either since it's well above 10k% difficulty which you will never reach in normal gameplay anyway.
Limitations of this article
I'm aware it would be nice with more mathematical - or just better explanations especially for non-swarms. I have tried to come up with a more precise model than what is described here, but it is pretty difficulty. The spawning system is based on a credit-based system internally and there is a lot of things I can't really figure out from the code that I can see. If you have more info than what is available in this article, please let me know in the comment section below.Credits for the contribution
The majority of the Final Swarm research was conducted by Spacious & Noll Reed.Suggest an improvement
Found something inaccurate or missing for Difficulty? Send us a message and we will fix it! Please be as specific as possible.
No comments yet. (If you left a suggestion or had a question, it will show up here once it's approved. You will usually recieve a reply to any questions within a day or two.)