After each victory players will be awarded a random number of "SunShard Fragments" the smallest piece there, 15 collected Sun Shards Fragments will turn into 1 SunShard, and 25 sunshards will turn into a SunCrest, which is a magical artifact that spawns a SunChest at Suns Temple. spawning a sun crest outside of suns temple will only spawn a chest that spawns a random amount of sunshard fragments, (fragments are still good if you made a mistake, this is good to get them back, since they are able to make suncrest weapons)

the rarest thing a suncrest chest can drop is sun up eggette or a Skill Gem

a sun up eggette randomly increases the players level by 1 - 15%
and a skill gem increases a skill eggs effectiveness with the skill linked to it.

both those items are four star Scarcely Rare (max rarity.)