Best Game Making Software?

As someone who actively develops with Unreal Engine, I would say Unreal Engine :p

But for real there are many reasons why Unreal Engine is the ideal game engine to use right now.

Free to use, low royalties you will have to pay when you make money from the game.

Much easier barrier to entry as far as not knowing anything and being able to quickly learn and start making things.
This is mainly due to it's blueprints system and the fact the amount of tutorials and resources out there to learn pretty much anything is quite vast.

Also it's updated so often and has the sweet Fortnite money constantly pushing it forward.