Terraria

Terraria is a mining, crafting and building game with RPG elements like Portal Knights, but it has a retro 2D style of art.

Ingredients, building blocks, furniture, armors, spells and weapons can be crafted, bought from NPCs or looted from enemies,

Although Terraria has ways of increasing the maximum health and mana with items, it has no direct levelling system and thus, no stat system like Portal Knights. There's also no class system, with bonuses depending mostly on armors, weapons and acessories, which provides easy respec of characters.

Even though there are similarities between the games, there is no connection between the developers of Portal Knights and Terraria.