Nintendo is bringing new items and modes to the best game of 2015.

Super Mario Maker gets an update on March 9 that provides new tools to change the way you make levels. Additionally, the build-your-own-Mario-course game is getting a Super Expert mode that will have you going through six hyper-difficult levels. You can only unlock this by beating the already challenging Expert mode. In 2015, Super Mario Maker was one of a few bright spots for Nintendo and the Wii U, and the company has said it will try to keep the keep in its customers’ minds by offering updates like these.

Super Mario Maker has sold more than 3.34 million copies worldwide, which is impressive considering the Wii U is only at around 11 million systems sold in total. It is one of the first examples of Nintendo building a game around user-generated content, and this has led to consumers designing more than 6.2 million courses for Mario Maker. The game is also the latest example of Nintendo taking a strong approach to games that get extra life through online functionality. After launching a successful multiplayer shooter in Splatoon earlier in 2015, the company continued the trend and is keeping Mario Maker fans engaged by treating it as a service that can always get something fresh and exciting.

The new items include keys and a locked door. You can put the keys in blocks or even in enemies. In these situations, you’ll have to beat an enemy to get the key to progress. This means you can design mandatory boss battles.

Keys are here!

Above: Keys are here!

Image Credit: Nintendo

Nintendo is also adding pink coins and a skewer. The pink coins will give players a key when they collect all five. The skewer is a giant, crushing obstacle that we first saw in Super Mario World.