Monthly Merge 15: Midnight Merge was the last Monthly Merge world for Supreme with Cheese, made by 4 Brave Nights.
Key of Lunacy is unlocked after getting all 4 Keychains.
Not So Fungi Forest (Day) (Hammer Keychain)[]
Rocket Keychain is in a secret passage in the pumpkin house after beating the Sea Cucumbers.
Otherwise, just mash enemies and grab candles till you leave level.
Not So Fungi Forest (Night) (Hammer Keychain)[]
Hammer Keychain is in a secret passage in the Shrooms and Zombies house.
Otherwise, just mash enemies and grab candles till you leave level.
A Fright to Remember (Pumpkin Keychain) (Night)[]
Note the Frozen lake compared to the day version.
Make it across,get into the cave, flip the switch to turn the lights on.
EDIT: That stupid top right box shifting puzzle.I just cheated through it anyway.
A Fright to Remember (Pumpkin Keychain) (Day)[]
Cross the lake and head into the cave, you will find yourself in a underwater environment. Go around flipping switches for candles and keys in this level to proceed.
Then in the next section, grab the Machete nearby and chop down the grass nearby for the Red Key and move forward.
In the next section, you will be ambushed by several Geozoids. Note if you run out of weapons, you can go back to the Underwater cave for a respawning free machete.
After beating the Geozoids, beat The Boiler and flip a switch nearby.
NOTE: For the Pumpkin Keychain, you need to beat The Boiler and destroy the wall to find a hidden passage to it.
After flipping the switch in the boiler room, go back to the geozoid room and flip the switches at the left, bottom left and top right.
EDIT: Alright, the top right switch push tile puzzle is a bit too hard to figure out, so i cheated through the level.
Strange Town (Day) (Squash Keychain)[]
EDIT: It's a very longish and tiresome level of questing around for coins to exit the level. I just cheated through it. I never figured where the Squash Keychain was.
Strange Town (Midnight)(Rocket Keychain Shard)[]
Check all around town on the inhabitants, which are acting like robots, then the middle door building which you find needs a Red Key. Then check the train station.
There's a Rocket Keychain part in the mailboxes in one of the buildings.
EDIT: Not clear how to get past this level and i have no time to remain stuck here so i cheated past it.
MIDDAY KOMBAT![]
As instructed by the beginning text, hold Z + left/up/down to control the tile character to kill enemies,kill enough and the level ends.
MIDNIGHT KOMBAT! (Rocket Keychain Shard)[]
Rocket Keychain Shard is at the bottom right of the level outside the grid.
All Candles are outside the grid.
Otherwise just watch out as this is a rather tough Zombie horde encounter,just mash them all and the level will end.