There are a total of 74 playable fighters in Super Smash Bros. Ultimate, and players only start off with eight of them - which means there are plenty to unlock, like Snake. With a total of 66 characters to unlock, there are mascots users would surely want to earn as soon as possible. For example, players may want to immediately unlock King K. Rool in Super Smash Bros. Ultimate, and this is sure to be the case for the Metal Gear Solid veteran Snake as well.
After missing out on the action in Super Smash Bros. for Nintendo 3DS/Wii U, Snake is a fan-favorite that's finally back in Super Smash Bros. Ultimate and ready to decimate the competition. Of course, this means that players will have to unlock Snake since he's not included as one of the eight initial characters. Fortunately for fans, it's possible to ensure that the tactical espionage expert is amongst the first fighters added to the fray.
As it turns out, the first step to take in unlocking Snake quickly is to jump into Classic Mode as Link from The Legend of Zelda: Breath of the Wild. Completing this mode will earn players King K. Rool, who players now have to use to clear Classic Mode in order to unlock the Ice Climbers.
Essentially, this method kicks off a small chain of fighter unlocks in Super Smash Bros. Ultimate that will eventually lead to Snake, but it's important to note the following order for anyone utilizing this method: Link > King K. Rool > Ice Climbers > Simon > Meta Knight > Snake.
For those uninterested in spending time in Classic Mode, it's also possible to find Snake in Super Smash Bros. Ultimate's story mode, World of Light. He can be found in a Metal Gear-styled base in the Southwestern portion of the World of Light map, where players will have to defeat several Spirits before being able to encounter Snake.
Anyone that would rather expedite the entire process can also just unlock every character in Super Smash Bros. Ultimate through a reset glitch (though it's unclear if it still works thanks to the Day One patch), but seeking out characters and earning them as intended adds a nice bit of nostalgia for longtime Super Smash Bros. players. For anyone that's a fan of the latter option, this guide should help.