We will have a more complex combat system in future (but that is polishing, for now we need to ensure that the core system works), for example shields will have all a certain defense skill/spell. We want to add a companion, which means you will be able to find small creatures which will passively assist you in combat and follow you everywhere. There will be more enemies, some which will use skills/spells. And you will be able to carry a certain use-item which will have an active skill/spell with a certain cooldown.
We do not want to implement a traditional class system, this game will go more into the direction of binding of isaac. In future you will be able to influence your playstyle by the decisions you make and the items you find.
In your old comment you mentioned some spells, they are all possible in our game, but they will be bound to an item or weapon, which means you will be able to have max. 3 active spells of a kind. For examle if you feel like playing tanky you could use 2 x shields and a defensive active item, where each has an active defense skill/spell.
Under the controls image is a description with all features which are planed for the full release.