Renounce the Guilds

[ELLERfeller]

Would duel lands like guild gates be sacrificed or would they still be colorless like basic lands?

[Sardok]

All lands are colourless unless specifically stated otherwise (i.e. {Dryad Arbor}).

[redwolv]

 {Renounce the Guilds}

[Kaylesh]

As Sardok said, lands are colorless.
Rules text does not grant colors to permanents.