SpiderHeck

You can get this as soon as you load up the game just spawn in and head right and halfway up the screen you'll find an entrance to the secret maze area, you'll unlock one achievement for finding the area then another for getting to the end. I'll post a video and just explain what I'm doing as a text guide below.

First off, the ceiling is your friend, unless specified you should always be swinging off the ceiling through this maze as you'll get a much slower controlled swing, anyways start the maze by swinging from the ceiling on to the stop platform, swing up to don't do it then jump and swing to the other side, jump off and grab the ceiling then fall left to land on I warned you, walk around to the gap and drop down to Is this fun?, this is the tricky part, line yourself up with the ? and ceiling swing twice to get up to give up, now go around and line yourself up with the G and jump swing around and once you reach the bottom swing onto congratulations?, now ceiling swing your way over to the right and climb up to the top, from the top jump to the first why, go to the top left corner making sure your spider is angled to jump diagonally to the second why, now go half way up the left side, jump and ceiling swing a little to the third why, another angled jump from the top left corner to the fourth why, go to the bottom left, jump and ceiling swing to the the fifth why and finally one more top left angled jump and swing your way around to the tinybuild logo, achievement should pop as you walk around to the top of the logo, enjoy!