I didn’t like him too much during his season as a villain.
At first we think he’s magical being to taunt Rumpelstiltskin while he tries to wake up Belle during her cursed dream. Turns out that he’s their unborn son, who already hates his papa.
Belle gives birth to him, gives him up for his happiness, and he’s taken by the Black Fairy later and is raised where time and space are different.
So he comes back as a jaded man who wants to take Emma Swan’s powers or something.
But he never seems to have enough power to do much and in the end, he loses.
But luckily for all of them, he’s turned back into a baby and gets a fresh start.