Bloons TD 6

In order to unlock this, go to the map Candy Falls. The easy bit is that you dont have to play any waves, place any towers or anything, you can do this, quit the map and get the cheve! But, that said, you have to click certain areas of the map, in order, with a 1 or maybe 2 second gap inbetween otherwise you get a small musical noise to let you know the pattern has reset. You can tell if youve clicked the right spot because a monkey that looks like an Oompa-Loompa from Charlie and the Chocolate Factory appears, and a couple of notes from THAT song play, which is why it has to be in order to hear the whole song!

The pattern for this is as follows:

1) Top right corner of the map (base of the white tree with green leaves)
2) Door of the House
3) Mist at the bottom of the chocolate waterfall
4) Top left corner of the map (the M-tile on the ground is a good spot)
5) Bottom bridge over the river, clock the top right fence-post/ wafer stick
6) Bottom right corner, click the spot where the orange tree leaves and left pink tree leaves meet
7) Centre of the water wheel attached to the house
8) Finally click the bottom left corner, theres a small pink pearl next to the track that works well

This should play all the notes, quit the map and the cheve is yours! (plus a cosmetic Small-Bloons extra is unlocked!)