This achievement is obtaned by getting a best weapon by Suckerstones.
Weapon must be at level +3 to start upgrading by sucker stones.
Weapons must be strengthened by Sucker stones up to a maximum of level 5.
Below are weapons that require the lowest ammount of ore to get final upgrade:
(Shard/Chunk/Pure) Suckerstones required
Claws: Dropped by Assassins in 1-3 and 1-4 (15/6/1)
Pickaxe: Sold by Filthy woman in 5-1, 5-2 (25/9/1)
Best places to find Ores:
Suckerstone shard: Dropped by Phosphorescent Slugs in 4-2, 5-2
Chunk of Suckerstone: Dropped by Phosphorescent Slugs in 4-2, 5-2
Pure Suckerstone: 5-3 Archstone, treasure, dead body in plague swamp