Super Filly Adventure, The "blank flank" ending (SPOILER)
To get the ending:
Step 1: Change system time to something between 11pm and 5.59am

Step 2: systematically go through all the screens, talking to everyones multiple dialogues. 

Step 3: make the good muffin (click the left ingredient everytime)

Step 4: give derpy the muffin, complete all exra dialogues

Step 5: Go talk to Zecora, then go right