Obsidian Conflict is a cooperative multiplayer modification set in the Half-Life 2 universe. It features a large amount of new gameplay features on all-new maps specially designed for the mod with focus on cooperative gameplay, as well as over hundred user-made maps following the same formula. In addition to that, You're able to play through vanilla Half-Life 2 all the way up to Episode 2, as well as experimental support for cooperative Half-Life: Source play.
Looks bland. Maps aren't supposed to look like they were made out of brushes, like that brush on the top.
That map would be perfect for HL2DM, if the sand was removed as well as ways to get on it closed off.