You need both in your party. Same applies to Rayquaza, Giratina, Kyurem and Landorus that need the other two pokemon of their respective trio.Does anyone know if you need Entei and Raiku in your party to capture Suicuine? Or just in the box?
Played around the Ultra Wormholes for a few hours and I think I'm getting the hang of it. Highest I've gone so far was over 3,000 lightyears. What I got from going through different wormholes:
-Several UBs except Guzzlord (been trying to aim for that at the moment)
-Two shinies (Crustle and Magcargo)
-Five legendaries (Regice, Raikou, Cresselia, Xerneas, Zapdos)