It was already announced that the upcoming Link Amiibo figure will be compatible with Hyrule Warriors, but now we have concrete details on how it will actually interact with the title.
According to Nintendo, when players place the Link Amiibo on the Wii U GamePad’s NFC reader, they will unlock the Spinner from The Legend of Zelda: Twilight Princess. Just as in its native title, the Spinner will allow players to barrel through waves of enemies. Koei Tecmo has confirmed that the Zelda Amiibo will also unlock a new weapon, though what that weapon will be remains to be seen. Tapping other Amiibo figures on the GamePad will grant players additional materials and Rupees.
Amiibo compatibility will be added to Hyrule Warriors via a software update later this month.
Source: Siliconera