I was looking through some of the games over at Gamejolt the other day and I noticed an interesting program at the top of the RPG section called the Encased RPG Engine. It's an engine designed for use with the game-making program Game Maker and it sets out the basic systems required to create a top-down, hack-and-slash RPG. Given that it comes with fully-functional inventory, melee combat and ranged combat systems, it looks like a perfect engine for people to use if they want to make anything remotely similar using Game Maker.
I gave the game that comes with the engine a play-through and it is pretty basic (as you'd expect) but everything seemed to work how it should. I have to admit that I was pretty impressed! In fact, if I was more experienced with Game Maker I'd be tempted to see what I could do with this engine because everything you need to get a game started is already there.
That's a lot of monsters to be dealing with - you can barely see the hero swinging his sword!
The engine is only v0.1 right now so I kinda hope that more features will be added as the developer continues to work on this project. For people wanting to make a hack-and-slash RPG it may well become a go-to engine because Game Maker allows you a lot of flexibility outside the engine's initial framework, meaning you won't be restricted to what you start with given you have an understanding of how Game Maker works. To be honest, the engine kinda reminds me of the Shoot'Em Up Construction Kit you could get for the C64 (I really am showing my age when I start talking about those) and just look at the stuff people managed to do with that engine!
If you're looking to use Game Maker for anything remotely related to this style of RPG then I suggest giving this a go, even if you only use it as a tutorial to help bulk up your knowledge of the Game Maker program!