Sawtooth pacing
Also said as Sawtooth difficulty curve, Peaks and valleys
Difficulty that climbs, drops, then climbs higher, like the teeth of a saw. Each hard stretch ends with an easy one, and the overall trend keeps rising.
A straight ramp means ever-growing strain. A drop after each peak gives relief and a moment of feeling strong, and it is often the place to introduce the next new idea safely.
Say it
“Use a sawtooth across the world: each of the four levels harder than the last, then drop back to about 60% for the first level of the next world and introduce the new enemy there.”
Where you’ve seen it
Where's My Water? works this way: each set of levels gets harder until you finish it, then the next set eases off before climbing again.
Not to be confused with difficulty spike
A spike is one unplanned jump with no build-up. A sawtooth is a pattern of planned rises and planned rests.