Each of these rings will help stave off lingering damage
Ring slot item – Uncommon
Effect: Each of these rings is attuned to a particular energy type: Fire, Ice, Lightning, Thunder, Acid, Poison, Radiant, Necrotic. A character wearing this ring gets a bonus to saves vs. ongoing damage from that element. As the tier goes up, more qualities are added (effects are cumulative):
Level 2: +4 bonus to saves vs. ongoing damage from that energy type
Level 12: the bonus counts for combo ongoing damage, so long as one of the damage types is the same as the ring’s
Level 22: the character may save vs. ongoing damage that this ring grants a bonus against at the start of his turn, immediately before the damage is to happen, in addition to at the end.
Each of these rings is carefully inscribed with runes, pictures, and stylizations that fairly obviously tie it to whatever ongoing energy type it helps to discontinue.
There are rumors of a sect of wizardly jewelers who managed to create a version of this ring that applied to untyped damage or even all ongoing damage, but such rumors are likely fanciful stories, and such an item would certainly be quite Rare (or even unique).