With older Legend of Zelda games, there was a limit to what items you could use at a time, and this game will be no different. However, when certain items are used along with other items the effect of the items being used will be much different.
For example, the Mallet can be used for a few different reasons, damaging specific enemies, solving certain puzzles and clearing out types of Obstacles, but for the most part it's a Hammer! Sure, you can attack with it, but you pretty much just hammer things with it.
But, should you then decide that you would like to use the Mallet with another item instead of your trusty sword, like say a bomb, the way the Mallet is used is much different and in a way that can trigger switches and be used in different types of puzzles. (thought I won't say exactly what that combination does, I can't spoil everything can I?)
This adds a certain level of complexity to the game that I really hadn't thought about, but I think really is going to add something more to the game than just being a normal adventure game with monsters to beat on.
In a lot of ways I want to recapture the feeling the original Legend of Zelda had with making the player have to explore around the world and look for clues. In later Zelda games, the object of exploration became less and less of an emphasis, and I always missed that.
There was something really fun about bombing random walls, or burning trees in hopes of seeing them fall away to reveal a cave opening, or a hidden staircase, and that's something I really want to bring back. There's something exciting about finding something in a far off corner that's entirely hidden from view that you found on your own.
Not only that, but I want people to really have to think about their play styles, and the items they are using and make sure that an item is always useful.
Many different adventure games that are based around items and their mechanics always seem to have 1 or 2 items that really just sit there in your inventory and never get used and this is something I really wanted to avoid. I always want an item to have a purpose that you'll need to use it for, and I never wanted a item to be "padding" for the game and just be something that you forget about.
I also definitely want to make sure that the puzzles are far beyond pushing blocks, and bombing cracks in the walls, and I really hope that the Item mechanics and the puzzles will really help the game stand out on it's own.