Heroic Maps gives you more options for terrain with the release of their Dungeon Core Set.
From the release:
Dungeon Core Set contains 25 generic geomorphic tiles that will allow you to build a simple yet extensive dungeon.
Dungeon Core Set is a printable geomorphic tile set, compatible with any RPG/Dungeon-Crawl game.
Dungeon Core Set contains 25 unique 6×6 geomorphic tiles that can be arranged in thousands of combinations.
Also included is a set of 300dpi full size jpgs, for poster printing or VTT. Please note that the pages are set as A4. You’ll need to adjust if printing on US paper.
Please note – a preprinted version will be available soon