Surprised you never heard of Clickteam Fusion before...?!? :o
I know you had to have heard of the very popular game called "Five Nights At Freddy's".. Several sequels have been made and the author Scott Cawthon made millions off those games and several things have been made off of it. T-Shirts, Toys, collectables.. And soon to be a major motion picture movie too! All those popular games got millions of downloads off of the Apple Itunes Store, Google Play Store, Steam and many other game distribution outlets to mention a few! Type into a google search the name Five Nights At freddy's and you will receive nearly 44,000,000 hits!! Clickteam has been around a very long time and was here way before Game Maker Studio, Construct 2 & 3 and all the others. Clickteam is the original pioneer of the drag & drop game making authoring tool way before the others ever existed!! Read below...
Check out the link below:
https://en.wikipedia.org/wiki/Five_Nights_at_Freddy%27s
If you do some research you will find that Clickteam Fusion is a very popular Game design tool and even the developer Asley Gullen from Scirra Software based all his designs from Clickteam which he himself was a user / developer before he created Construct, Construct 2 & 3.