The Stack

One of the larger (but not the largest) of the very large levels in The Second Sky‘s eleventh chapter is all about Fluff so let’s talk about Fluff. Fluff is depicted as cottony white clouds, but these clouds are as impassible as any other obstacle. It’s like tarstuff, in that it needs to be two tiles thick at all points, and when it isn’t, the thin parts break off into monsters, called Puffs. Or maybe it’s wrong to classify Puffs as “monsters” — they don’t count as such for level completion. Sometimes completing a Fluff room means fleeing just before the massed Puffs overwhelm you. Which they can do, because, like Wubbas and Serpents, you can’t hurt them with your sword.

Oh, they’re not unkillable. Explosions will take Puffs out, and if you have access to a pushing weapon, you can crush them against walls or obstacles, including other Puffs. Similarly, Fluff can’t be cut with sharp weapons, but only with blunt weapons or explosives. But not all Fluff rooms provide these things. Instead, the chief weakness of Puffs is that they’re slow. They only move once every five turns. They’re the only creature with this property, and it completely changes how you deal with them in puzzles. Among other things, it means they can’t cross Hot Tiles unless they’re pushed. Leading a Puff to an opportune spot involves a lot of waiting, and often you have to deal with other things while you’re waiting, so it’s more like just making sure you wind up in the right place relative to the Puff after every fifth turn.

Fluff, I say, is essentially a tarstuff, but it’s a peculiar form of tarstuff. It’s the only form of tarstuff that flies; in both Fluff and Puff forms, it can go over pits and water, and doesn’t trigger pressure plates. Also, there is no such thing as a Fluff Mother. Instead, there are vents, an architectural feature that cannot be killed. If a vent is covered by Fluff, then that Fluff expands every 30 turns by the normal Tar Mother expansion rules. If it’s not, then the vent simply emits a Puff instead. But vents tend to become covered by Fluff over time, because of Fluff’s most notable unique feature as a tarstuff: it can reform. Puffs adjacent to Fluff can merge with it. If four or more Puffs gather in a tar-stable shape, they meld into new Fluff.

I think the most important thing about Fluff, though, is that it hates all life. Puffs are the only thing that will actively pursue and kill both the player and the monsters — which is another good reason for excluding puffs from the “monster” category, because they don’t kill each other. (Slayers will sometimes kill monsters in pursuit of the player, but only because they’re in the way. They don’t hunt down monsters the way Puffs do.) There are multiple rooms with no monsters other than Puffs and the passive and immobile Brains, where your goal is to bring them together.

The great thing about all these unique features is that so many of them can be used in puzzles as either obstacles or solutions, depending on context. Puffs being slow is a good thing, until you need to get them somewhere within a time limit. Puffs attacking monsters is a good thing, unless you need the monster alive to weigh down a pressure plate or something. Puffs forming into new Fluff is good if you need to create an obstacle to keep that monster standing on the pressure plate, but bad if it blocks your only way out of the room. Vents are bad if they fill the room with inescapable Fluff, but good if they’re the only way to kill monsters. This is rich puzzle fodder, exactly the sort of thing DROD thrives on.

If a Puff dies over water, it lets out a burst of cold that freezes its tile into thin ice, which is equivalent to a trap door: you can walk on it once, but it collapses as you step off. I learned this in the first Fluff level, but there’s so much about Fluff that’s peculiar that I had completely forgotten this one detail the next time I needed it. I think this is the first time I’ve found the monster descriptions in the help menu really useful.