Scratch is good for prototyping, it has an okay programming logic system, good enough to create frogger and simple maze games.
It's used in some schools to teach kids programming logic.
Yes, if you want to start making games you have to start somewhere, Scratch gets very complex if you try to go beyond the basics, for example moving and making simple collisions can become a problem. Have a look at their site and see it for yourself.
2 Clickteam fusion
This game engine managed to survive the windowXP era, the game engines is usually advertised as gateway for beginners, the reality is different. The software has a steep learning curve, once users make the $399 purchase, they're often left in limbo, scrambling for tutorials created by the community, these tutorials are often created by other users who aren't necessarily experts. Official help and guides are paid only, the company creates paid tutorials for the public.
Clickteam fusion relies on extensions created by the community which have no support, as the software gets updated many of these extensions stop working. These extensions are needed since the software native movements were developed for windows 3.1.
$399 gets you the main software which saves windows games only, saving game for android will cost you another $129, $149 for iOS, $79 for HTML5 and so on. This game engine is okay as a hobby, not recommended for beginners or professionals.
This game engine is also advertised for beginners and easy to use. It's worth mentioning that this game engine is geared towards the iOS market and it's absolutely terrible for creating android games and PC games.
You can build windows and android games but the developers have given more priority to iOS game development.
The software is also subscription based which in itself it's not a bad thing but for the engine can do, some feel it's not worth the price.
Many people find that programming logic in this game engine can get confusing very quickly, finding Stencyl tutorials can be a bit of a problem since there aren't many people making tutorials for this game engine, the number one complaint about this software package is its poorly made help file.
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