Les cinq cartes Zetalpa, Primal Dawn, Nezahal, Primal Tide, Tetzimoc, Primal Death, Etali, Primal Storm et Ghalta, Primal Hunger, ainsi que Zacama, Primal Calamity, de l'édition Rivals of Ixalan, forment un cycle de dinosaures et ancêtres légendaires appelés "Mégasaures".

Source 1 ("They're Back!") - Source 2 (Etali, Primal Storm) - Source 3 (Nezahal, Primal Tide - Ghalta, Primal Hunger) - Source 4 (Zetalpa, Primal Dawn - Tetzimoc, Primal Death - Zacama, Primal Calamity) - Source 5 ("Much like we make a cycle of Dragons in a Dragon set [...] they made a Dinosaur cycle") - Source 6 (Ghalta, Primal Hunger - Zacama, Primal Calamity)