hasbrotoyshop on ebay store is having discount on some dropmix packs.
I found 5 of them having between like 60% off to 73% off. Good for someone who started on the core cards and wants to expand.
$4
https://www.ebay.com/itm/DropMix-…4b5782cb7c
$5
https://www.ebay.com/itm/DropMix-…4b5c3303aa
$5.19
https://www.ebay.com/itm/DropMix-…4b599b202e
$11.99
https://www.ebay.com/itm/DropMix-…33ec709338
$11.99
https://www.ebay.com/itm/DropMix-…4b45c207af