What is dynamic difficulty adjustment? How Crash Bandicoot secretly goes easy on you
Dynamic difficulty adjustment (DDA) is a hidden system that makes a game easier while you play, based on how you are doing. In Crash Bandicoot, if you die a lot, the game gives you a free mask, turns a crate into a checkpoint and slows the boulder down. Strong players never trigger it, so their game stays the same.
What the game is doing
The game counts how often you fail, and only steps in when that number gets high. In Crash Bandicoot, Naughty Dog's co-founder Jason Rubin describes three kinds of help:
- A free mask. If a novice player died many times, the game could give them an Aku Aku mask at the start of a round. The mask takes one hit for you.
- A new checkpoint. If you died too much, a plain fruit crate would suddenly become a continue point. You restart closer to the hard part.
- A slower boulder. In the boulder chase, the game slowed the boulder down a little each time you died, so the gap to Crash grew.
The help comes in small steps. Each extra death adds a little more. Players who rarely die never see any of it.
Why it works
A fixed difficulty only fits one kind of player. Rubin points out the problem with fixed continues: they make players who need lives fail, and they bore players who don't. Beginners hit a wall and quit. Experts walk through and get bored.
DDA moves the wall instead of the player. Every person plays a slightly different version of the same level, tuned to them. And because the help is quiet, nobody feels talked down to. You don't see "easy mode switched on". You just finally make the jump, and the win still feels like yours.
The key is the rule Naughty Dog used. In Rubin's words, the aim was to "help weaker players without changing the game for the better players." Help that only reaches players who are struggling costs the good players nothing.
Real games that use it
- Crash Bandicoot (Naughty Dog). Jason Rubin explains the free mask, the crate checkpoint and the slower boulder in Andy Gavin's Making Crash Bandicoot, part 6. The team called it DDA, Dynamic Difficulty Adjustment.
- Crash Bandicoot N. Sane Trilogy (Activision / Vicarious Visions). The remake's official blog post Go Ahead and Jump! says the game gives Crash masks and checkpoints after a certain number of failures in a level. The same post says DDA was first only in the second and third games, so the sources differ on which original game had it first.
Neither source gives an exact death count, so we don't either.
How to use it in your game
Start simple: count failures per section, and give help in small steps once a threshold is passed.
int deathsHere = 0;
void OnPlayerDied() {
deathsHere++;
if (deathsHere == 3) GiveShieldAtStart(); // one free hit
if (deathsHere == 5) MoveCheckpointCloser();
if (deathsHere >= 5) chaser.speed *= 0.95f; // a little slower each time
}
void OnSectionCleared() {
deathsHere = 0; // reset, so help never carries into the next part
}
Tips:
- Count the deaths in one place. Reset the counter when the player clears that section. Help for one hard jump should not make the whole game easier.
- Help only past a threshold. A player with zero deaths should get nothing. That is what keeps the game the same for strong players.
- Use small steps. One shield, then a checkpoint, then a slightly slower enemy. Big jumps in help are easy to spot.
- Don't announce it. The point is that the player still feels they won.
- Never use it in competitive modes. Secret help for one player is unfair when two people play against each other.
- Playtest with real beginners. Watch where they die most. That is where your thresholds should sit.
FAQ
Is dynamic difficulty adjustment the same as a difficulty setting?
No. A difficulty setting is a choice you make in a menu before you play. Dynamic difficulty adjustment changes the game during play, based on how you are doing, usually without telling you.
Did Crash Bandicoot really get easier when you died?
Yes. Naughty Dog's co-founder Jason Rubin describes free masks, crates that turn into checkpoints and a boulder that slows down after many deaths. Activision's blog confirms the masks and checkpoints in the N. Sane Trilogy remake.
Does dynamic difficulty make games too easy?
Not if it only helps players who are struggling. Naughty Dog's rule was to help weaker players without changing the game for better ones, so good players never see it.
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