Path of Exile

Shaper orbs are items you can get by completing specific maps bonus objectives. They will increase the tier of a map 5 tiers below the dropping tier by +5 (eg orb dropped in tier 7 turns a tier 2 map into tier 7). These orbs change every future map drop into a shaped map. They are applied directly to an atlas. Orbs only work on 1 map at a time, so pick wisely. Keep in mind that a bonus objective will require the map to have a specific rarity (yellow maps - rare, red maps - corrupted rare).

Below is a list of maps and tiers where you can find shaper orbs.

Tier 6-Spider Forest Map
Tier 7-Ashen Wood Map
Tier 8-Bog Map
Tier 9-Reef Map
Tier 10-Colonnade Map
Tier 11-Excavation Map
Tier 12-Estuary Map
Tier 13-High Gardens Map
Tier 13-Oba's Cursed Trove
Tier 14-Volcano Map
Tier 14-Poorjoy's Asylum
Tier 14-Death and Taxes
Tier 15-Overgrown Ruin Map
Tier 15-The Vinktar Square
Tier 15-Vaal Temple Map

As of 3.17 (Archnemesis League) with the Atlas passive tree rework the decription hasn't been updated but the unlock conditions for this achievement have changed to:

"Apply an Awakened Sextant to a Voidstone."

You can get Voidstones from certain pinnacle bosses in the end-game and Awakened Sextants drop at random in Atlas content

Since Conquerors of the Atlas (3.9), the achievement requires you to socket a Watchstone in any socket on your Atlas. Watchstones are dropped by killing Conquerors in an Atlas region where you haven't killed them before, with the first one coming from Baran, the Crusader.