With an engine (And not a game maker like FPSC), it's not about Single Player or Multiplayer.
You have to PROGRAM the single player and multiplayer aspects of the game you want to make.
If you want to use Leadwerks, then you can expect to spend at least 50x more time in making a single game than with FPSC. This is especially true if you need to learn the programming language first.
FPSC does a whole lot of stuff for you that people take for granted (and usually complain about). This includes movement routines, firing your weapon, loading media, handling lighting, reading in AI scripts and processing them.
I can't imagine that Leadwerks will do all of that for you. But from what it's been showing off, I can see that it handles lighting and physics for you. You'll probably need to worry about doing the AI of enemies yourself, as well as player movement, player shooting, enemy shooting, picking up items, etc etc etc.
I hope no body here is under the misinterpretation that Leadwerks is going to be nearly as easy to use as FPSC.
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