Rank-Up 5-Star Goblin (unduped) or 4-star Starkey (Duped lvl-19)
Love Starkey, he's part of my Attack Trio... but I know Good 5-Stars will take me further in the game!!!! AND it will be awhile before I have 3-Four-Star Tech Catalysts again!!!
If you can provide good reasons for your choice, I'd deeply appreciate anything you say!!!