Last week I headed to Nintendo's UK base to hear a bit more about the game and experience the single-player firsthand. Where Smash Bros. has been undeniably one-dimensional in the past, Nintendo wants this one to be a bit more accessible. Basically, the idea is that when you're not taking names online or among friends, there's other stuff to do. Maybe you're just not that competitive to begin with. And it doesn't matter if you never indulge in a multiplayer brawl. However you want to play the game will be rewarded with new characters, stages, etc.
There's what you'd call a classic arcade mode, where you take on a handful of computer-controlled opponents in successive one-on-one bouts until you reach a huge, unplayable boss type. At the beginning of your run you select a difficulty from 1-10 and it'll dynamically adjust between matches based on your performance, so it should never be too hard. The boss could be a robot dragon or some other cartoonish monster, and there are rare ones for particularly hard, clean runs. You negotiate their attack phases like your standard platformer bosses until you wipe out their health bar. If you die, no big deal. You can just continue from the moment you died.
The meat of this new focus on single-player fun is a sort of campaign called "World of Light." I believe there's some far-fetched story attached to this -- I wasn't party to any opening cutscenes -- but the basics are: You walk around a Super Mario World-style map jumping from one battle to the next, collecting what are called Spirits. So... Spirits are characters from video game lore that are represented by Smash Bros. fighters with certain special characteristics. The Spirit of a Guardian from the latest Zelda game, for example, could be represented by a Mario with a permanent metal power-up.
It's hard to explain because you kind of have to just go with it. In one Spirit battle, you might have to fight ten weak Peaches because that's vaguely relevant to some character from Advance Wars, or one large Donkey Kong who is particularly susceptible to projectile attacks because Pokémon. Whenever you win a battle, you collect that Spirit and add it to your library. You can then assign that Spirit and it'll either passively or actively buff your fighter. It may also have its own slots you can fill with secondary Spirits that have their own advantages. The Spirits gain levels the more you use them, and a separate currency earned through successful battles can be spend on a skill tree that provides yet more character buffs.
Each battle is almost like running into Pokémon Trainer, but you get to see what you're up against beforehand. The Spirit battle might feature say, Fox, and he does more damage than usual, but he's also slow and is really fond of his up + special attack. He also has a weakness to weapons, like swords and mallets. You start World of Light as Kirby, and slowly unlock more characters as you traverse the world, but let's say I use Kirby for this fight. I'll look through my Spirits and find one that reduces damage taken (to account for Fox's damage increase), and also has a slot so I can equip a secondary spirit that puts me into the fight with a laser sword already in hand (taking advantage of Fox's weakness). I can keep my distance with the sword, do more damage with it and I don't really need to worry about anything else, because Fox is more sluggish than usual as it is and his up + special attack has a long start-up time, so I can dodge or counter it easily.
That's basically how every one of these fights goes. You look at the strengths and weakness of the opponent, equip Spirits to counter or exploit them, rinse and repeat. You can press a single button and let the game auto-equip the most appropriate Spirits for you, and you'll be warned if what you've manually selected isn't right for the battle. It's an idiot-proof system, which is great if you can't be bothered with the Spirit admin. But then what's the point if the strategic element can be ignored with one button press?