Oh, Sonic. When the speedy blue hedgehog first appeared on the Sega Genesis 24 years ago, he seemed so cool: his debut game was similar to the competition's portly plumber, but with a speed and attitude all of his own. Who would've imagined that it'd be all down (green) hill from there?

These days, Sonic is best known for a decade's worth of shoddy spin-offs, a whole slate of failed reboots, and multiple forums' worth of comically inept - and occasionally terrifying - fan art. Maybe Sonic's not relevant any more - or maybe, just maybe, colorful anthropomorphic mascots simply don't belong on modern-day consoles. Maybe, in this day and age, they're better suited to mobile platforms.

After all, mobile's worked out pretty well for those pesky Angry Birds, whose physics-based puzzle games (and associated spin-offs) have made developer Rovio one of the wealthiest companies in the world. Now, Sega and Sonic are trying to capture some of that Rovio magic, with the announcement that characters from Angry Birds Epic will appear in Sonic's mobile-based infinite runner, Sonic Dash.

For a limited time, Sonic Dash players can earn coins that will permanently unlock characters from Angry Birds Epic - specifically, Red, Chuck, and Bomb; players with deep pockets can also access the Angry Birds with real-life money. The promotion is timed, but once unlocked, the Angry Birds will stay in Sonic Dash indefinitely.

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Everything about this deal is weird. Sonic Dash premiered on Apple devices a little over two years ago, and while critics praised its simple controls and faithful use of the Sonic license, many complained about the game's aggressive play-to-win business model. Despite mediocre reviews, Sonic Dash is fairly popular - it's been downloaded over a million times.

Meanwhile, Angry Birds Epic is turn-based role playing game in which the Angry Birds dress up like knights and wizards and embark on a fantasy adventure. Yes, seriously. The game also has a fairly deep crafting system.

Endless runners and role-playing games aren't anything alike, making this a strange crossover, and Angry Birds' popularity has waned over the past couple of years. Rovio's trying to combat its falling profits by branching into other forms of media (including, of all things, young adult novels), but it's hard to tell if that's working.

Honestly, this doesn't seem like it's going to do much to help either franchise. Like Sonic, Angry Birds came out of the gate strong and struggled as time went on. And like Sonic, it's easy to imagine the Angry Birds becoming something of a joke - the kind of thing people will look back on in ten years while shaking their head. That first game was popular enough that the Angry Birds won't go away entirely, but as Sonic proves, that fall can be pretty brutal.

Sources: NeoGAF, The Verge