A writhing mass of toxic, sentient slime oozes menacingly towards a village. This foul red substance—the titular Xenospore—consumes anything it touches, leaving a trail of crimson-coloured devastation in its wake. The pixel art in this indie puzzler may be simple, but you can almost smell the sickly, bubbling alien gunk as it squirms across the map hungrily devouring entire towns and cities. Worse yet, the only thing standing between it and the end of the world is you.

Not enough puzzle games are sinister. That's why I love Xenospore, which you can play for free in any web browser. Created by solo developer AvivL, it's a wonderfully simple game, played entirely with mouse clicks or taps of your finger. It's replayable, deceptively challenging, and deeply satisfying—everything a great puzzle game should be. But it's deliciously disturbing too, with a dark, moody atmosphere that reminds me of grimy '80s sci-fi horror films.

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As the infestation creeps gruesomely across an isometric map, you have to strategically destroy tiles to stop its spread. Every time you make a move, the Xenospore grows and infects more tiles. If it manages to reach a settlement, you can sacrifice a turn to 'cleanse' it—at the risk of the spores spreading further. Keep at least one settlement from being destroyed and you win, but the real skill, and satisfaction, in Xenospore lies in saving them all.

Xenospore

Things get even darker when you find yourself being forced to sacrifice one settlement to save another. Sometimes the only way to pass a level, if you've backed yourself into a corner, is to let a city be eaten by the creeping rot. Occasionally text floats above settlements in the process of being destroyed,which are, harrowingly, the cries of the helpless citizens within. "There's nowhere to run!" they'll yell as the blight consumes them. Told you it was dark.

I admire how streamlined Xenospore is. You can figure out how to play it in seconds just by clicking around—and with a little help from a few disguised tutorial levels. But as the maps increase in complexity, and the infestation grows more widespread, it becomes frantic. Trying to save multiple disconnected settlements scattered across a large area, with the looming threat of the spores always in the back of your mind, is stressful—but oddly fun too.

Xenospore

The presentation is also great. The pixel art is bold, stylish, and readable on busier maps. The grainy CRT filter, ominous, droning ambient music, and the way the levels hang in a black, endless void really heighten the sinister '80s atmosphere. Destroying tiles and clicking around the map feels nicely tactile and crunchy too. It's clear a lot of work has gone into fine-tuning how Xenospore feels, which is something I always appreciate in a puzzle game.

Xenospore is one of the most unique puzzle games I've played in ages. I love the premise of that merciless extraterrestrial sludge eating cities, and you having to step in and save them. But mostly I just love the vibe. It's weird, unsettling, and quietly unnerving—which are not words you'd commonly associate with the puzzle genre. I'd love to see AvivL expand on the concept in a sequel, with different types of infestation to deal with and other ways to fight against them.

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