This is kinda old news, but maybe some of you haven't heard this yet (considering that the game isn't very popular).
For those unfamiliar with the game, Spiral Knights used to gate its content by charging an in-game currency fee (Energy) for every level you play. Revives also cost energy, and the cost escalates at every revive per run. A small amount of Energy is given for free per day, but it was only enough for about 5 levels and a couple of revives. In addition to that, players needed a lot of energy to craft gear, which is the main character progression of the game. Obviously, players could buy more Energy with real dollars. This was a big turn-off for a lot of players, especially since the game can be a bit grindy.
A couple weeks ago, the game had a huge patch that introduced and revamped a lot of things -- among the things that changed is the energy system. There is no more energy fees to enter levels and craft! Players now get one revive for free per level, and additional revives come in the form of an item. Basically, we can finally play the game as much as we want without the free-to-play bullshit.
This makes now a pretty good time to try (or get back into) the game. I really like this game, but I haven't played the games in months because of all that energy crap. It's nice to finally be able to try out the rest of the game's content without having to worry about my video game financial situation.