The Coin Master

Head to the D-shaped fountain next to the bank in Dalaran at 45.57, 67.91 — this is the only fountain that works for this achievement. Fountains in other areas of Dalaran, such as Runeweaver's Square, do not count.

Stand a few paces back from the fountain's edge, casting from around 52, 65.5, to reduce the number of failed casts that land outside the water.

A vendor and fishing trainer are located right next to the fountain where you can buy lures. Once your fishing skill is maxed, you can use Bright Baubles instead of more expensive lures.

When you fish up a gold coin such as Arthas' Gold Coin, you can toss it back into the fountain to gain a 2-minute Lucky buff. Without the buff, gold coins drop at roughly 7% and silver coins at roughly 8%; with the buff active, gold coins rise to roughly 15% and silver coins to roughly 20%. Always check that your fishing lure has more than 2 minutes remaining before tossing in a gold coin.

Copper coins like Krasus' Copper Coin and silver coins like Alleria's Silver Coin can be sold to the vendor standing right next to the fountain when your bags fill up.

You must personally fish up every required coin — coins given to you by other players will not count toward your achievement progress. Expect roughly 350–500 casts total to complete all sub-achievements, with unlucky runs reaching around 500 casts.