You need four amiibo to get everything Metroid: Samus Returns has to offer
UPDATE: Standard hard mode accessible to all, as well as harder amiibo mode.
UPDATE 8/8/17 1.50pm: Metroid: Samus Returns will include a hard mode accessible without the need for amiibo - separate to the one unlocked using the "squidgy" Metroid figurine.
Nintendo shared the news with our friends across the ocean at USGamer. It makes the whole amiibo situation seem a little fairer - although you'll still be missing out on some fun extras without the game's four compatible figurines.
So, to be clear, there are two hard modes in the game. Hard mode, which will unlock normally after you complete Samus Returns, and then Fusion Mode, which is even harder and grants Samus' Metroid Fusion suit. The latter is the one you need amiibo for.
ORIGINAL STORY 8/8/17 1.50pm: There's a bunch of cool extras to unlock in Metroid: Samus Returns - but you'll only get them if you have four Metroid-themed amiibo.
The 3DS remake of Metroid 2 will launch alongside two new Metroid amiibo figurines - one for Samus, one of a Metroid - and will also be compatible with the two existing Smash Bros. amiibo figures for Samus and Zero Suit Samus.
Each of these four will give you something extra in Metroid: Samus Returns, and a Nintendo spokesperson has confirmed to Eurogamer that "this unlockable content is only unlocked using amiibo".
First off, the new Samus Aran amiibo which will launch with Samus Returns. This figurine of a crouched Samus will unlock an extra energy tank for you to use. After completing the game you'll be able to unlock exclusive Metroid 2 art in an art gallery.
Next, the new "squidgy" Metroid amiibo. This will let you reveal the location of any nearby Metroid on your map - something which sounds pretty handy. After completing the game you can also unlock a new difficulty mode, "Fusion", and where Samus' suit from the Metroid Fusion game.
Then the Smash Bros. amiibo. Samus will unlock a missile tank and after completing the game snag you exclusive concept art for your gallery. Zero Suit Samus will unlock another energy tank and after completing the game let you listen to Samus Returns' soundtrack of background music via a special mode.
These are great additions, although galleries of concept art and a sound test mode have been included in past games without the need for extra amiibo.
So, if you wanted everything Metroid: Samus Returns has to offer, how much would you need to fork out? Best case scenario, each Metroid-themed amiibo costs £10.99. Quadruple that and you're looking at spending £44 - effectively the same price as the game itself.