New Super Mario Bros.: 8-Fort 2

This Fort has snake platforms. It will take us past fire bars and spikes. At one point, there will be spikes on the ceiling and floor. Once you leave that area, quickly move to the very front of the platform, as it is going to rise up. You'll go through another area with spiked ceiling and floor. The first Star Coin will be in an alcove here. The midpoint is at the stone ledge on the left side. A small spike ball will appear and start rolling on the platform until it doubles back. There are Red Coins to get in this area. The platform will rise up to an area with fire bars. The second Star Coin will be nearby. When the platform comes out on the right side, hop back on, but be aware that another small spike ball is heading your way. Jump over it and get the third Star Coin. The platform will soon go straight up, so stay at the very front. It will take you to boss door. Bowser Jr. is wearing his mask and this battle takes place on a small platform in the lava. Defeat him and a bridge to Bowser's Castle appears. He takes Peach there.