A new rare land cycle in Throne of Eldraine offers some cool lands, but Castle Locthwain looks interesting for several Modern decks, such as Jund and 8-Rack.
Its draw ability works well in decks that empty their hand quickly, so this it requires a specific approach. Some players will find a way to fit this in Death's Shadow, too.
In either case, it will surely find its home in Modern. All we need is time to test it out properly.