That Was Wild! Achievement not triggering for Zixor Prime

I needed 5 copies of legendary beasts to complete the achievement. I copied Zixor, Apex Predator once. Then I drew Zixor Prime and copied it at least 7 times thanks to Brann, Dragon Breeder, and Zola copying the Tending Dragonkin. When the game was over my count for the achievement had only gone up by one.

Here’s the deck if it helps:

Custom Hunter

Class: Hunter

Format: Wild

2x (1) Fetch!

1x (1) Mystery Winner

2x (1) Rangari Scout

2x (1) Tracking

2x (2) Bargain Bin

2x (2) Birdwatching

2x (2) Dragon Breeder

2x (2) Explosive Trap

2x (2) Freezing Trap

2x (2) Messenger Buzzard

2x (2) Scavenger’s Ingenuity

1x (2) Titanforged Traps

1x (3) Brann Bronzebeard

1x (3) Exarch Naielle

2x (3) Stitched Tracker

1x (3) Zixor, Apex Predator

1x (3) Zola the Gorgon

2x (5) Tending Dragonkin

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