Sealock Monster can't attack unless defending player controls an Island.
{5}{U}{U}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
When Sealock Monster becomes monstrous, target land becomes an Island in addition to its other types.

• Number: 42
• Rarity: U
• Power: 5
• Toughness: 5
• Type: Creature
• Subtype: Octopus
• Mana cost: 3UU
• Color: Blue
• Artist: Adam Paquette