pokemon horsea card Japanese 116/165 sv2a TCG [Electric] x2 Retreat Cost Horsea (Aquapolis 84) - Bulbapedia,

I dont think theres a strong reason why Brawl shouldnt have a sideboard

This reinforces the idea that Eldraine doesn't necessarily play with exceptionally strong mechanics but rather that the cards from Throne of Eldraine in particular were much stronger than the kind of thing Magic is used to

And if want to draw cards to dig, most are running Harmonize, Fact or Fiction, or Sign in Blood to exile and draw

Blastoise ex TypePokmon Collector Number30 RarityDouble Rare Attacks Twin Cannons140 Discard up to 2 Basic Water Energy cards from your hand

Forget morphs, a little work and this card lets you cast Eldrazi for free