For a gold card to really shine in cube it has to be better than the alternatives
Legendary Creature - Human Warlock Counter Removal (CTRL to add secondary) Drain Syr Konrad, the Grim Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent
6 Nidoran Calling For Others Of Its Kind Nidoran may not have any Moves that can deal damage, but it can call out other male Nidoran from your deck and get them directly on the field
Aetherworks Marvel is another must-have in an energy deck
If one of the tokens can't attack for any reason (such as being tapped), then it doesn't attack
UB is a strange color identity for a sea creature deck, but Runo presents a fun mini-game to get it flipped, and Krothuss, Lord of the Deep is one of the best sea creature payoffs you could ask for