Sea Monster can't attack unless defending player controls an Island.
Related products
from $5.99
Lórien Revealed
The Lord of the Rings: Tales of Middle-earth
Draw three cards. Islandcycling {1} ({1}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)
from $1.39
Stern Scolding
The Lord of the Rings: Tales of Middle-earth
Counter target creature spell with power or toughness 2 or less.
from $3.89
Tolarian Terror (Foil)
Dominaria United
This spell costs {1} less to cast for each instant and sorcery card in your graveyard. Ward {2} (Whenever this creature becomes the target of a spe...
View full details
from $2.19
Hardened Scales - Borderless - Showcase
Wilds of Eldraine: Enchanting Tales
If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.
from $2.69
Decadent Dragon // Expensive Taste - Showcase
Wilds of Eldraine
Flying, trample Whenever Decadent Dragon attacks, create a Treasure token.