Resolve groups of content types

Hello there! I'm trying some Beamable features and I have some doubts regarding Content:
1.- First of all is there any way to resolve a complete group of content type? Let's say I have multiple armour items, all of them instances of the class Armour. Can I resolve all of them at once to get the complete list? A workaround would be to create another ContentObject class with a list of armours, but this doesn't look very clean to me.
2.- Following the previous mentioned workaround, looks like I'm having some issues with polymorphism. If I have multiple classes inheriting from Armour with different behaviours and different data, the serialization works fine, but when I download the content the deserialization fails, I'm guessing this could be related to Beamable not knowing which derived type to use for deserialization.

Any help or guidance would be much appreciated!!