Keruga, the Macrosage is a rare Legendary Creature — Dinosaur Hippo card from Magic Online Promos (PRM), collector number 80847.
Companion — Your starting deck contains only cards with mana value 3 or greater and land cards. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.) When Keruga enters, draw a card for each other permanent you control with mana value 3 or greater.