Gate

Gate is a nonbasic land type that is featured in the Return to Ravnica block. Gates are common dual lands that can tap for either of two different colors of mana (one for each guild). That it is a Gate doesn't mean anything on its own, but it's a marker that other cards look for.

According to Mark Rosewater the Gates play an important role storywise, but more so later in the block. They weren't supposed to pull focus early, there so we just had enough cards mentioning Gates to keep players from asking why the Gate subtype even existed.

Cards interacting with Gates

Return to Ravnica

• Armory Guard
• Gatecreeper Vine
• Ogre Jailbreaker