Each Synchro Monster lists its required Synchro Materials in the first line of its card text
Zetalpa, Primal Dawn Rarity: Rare TYPE: Legendary Creature SUBTYPE: Elder Dinosaur CMC: 8 Mana cost: USD: $0.23 EUR: 0.20 TIX: 0.02 EDHREC RANK: 1643 (4/8) Flying, double strike, vigilance, trample, indestructible Zimone, Paradox Sculptor Rarity: Mythic Rare TYPE: Legendary Creature SUBTYPE: Human Wizard CMC: 4 Mana cost: USD: $4.10 EUR: 3.46 TIX: 0.06 EDHREC RANK: 3405 (1/4) At the beginning of combat on your turn, put a +1/+1 counter on each of up to two target creatures you control
C Common Sol and Luna X SPELL Quick-Play Target 1 monster you control and 1 monster your opponent controls
The idea that an event is destined to happen and the struggle to avoid or accept it plays into the narratives of a lot of my favorite heroes, which is why I was delighted to see these concepts implemented in Kaldheim with the foretell mechanic
If upkeep effects are phased out of the game entirely, this pair will effectively cease to get new support