RTS of epic awesomeness...
That's also one made in Game Maker. While impressive, it's also a big resource hog. GM isn't very fit for some types of games, unfortunately.
Actually it's fine; what the problem is that a lot of people who use GM are too ignorant of how computers work *not* to load every single graphic and sound into memory on startup rather than to load it from file only when you need it. Even Glum Buster makes this mistake, every single graphic is loaded on startup, leading to 500 MB of used RAM. But it's perfectly possible to create games in GM that load only the resources you need for the current area, and that reduces the RAM it requires. Most GM games that only load resources when needed can keep their RAM usage below 100 MB.