Most of the Solars fight against the Abyss, and they are rare enough that the amount of existing Solars can be counted on one hand. Their culture is therefore strangely fragmented, though it exists; immortal beings that have observed the world for millenia, they tend towards egocentrism and obsession with their own power.
Most Solars, like many of the Planetar, wear complicated armor full of symbological meaning that mortal beings do not understand. The Solars speak Cosmic, the language of the Heavens, but many of them are ancient enough to speak several mortal languages as well. Solars have power over Fire and Light, and they combine it into Blaze, an element unique to their kind which can be damnably difficult to withstand.
It should be noted however that every solar possesses a large, amber jewel in their chest; made of relatively fragile material, it contains their crystallized 'soul', and forms their identity. Its destruction would rapidly lead to their eventual death.