First, an easy point: "Hela" seems to be quite recent. Her standard name is Hel. As for strength, it depends what you're trying to get done. Or where.
2 Answers · Society & Culture · 07/03/2013
Knockers,cobolds, dwarves, gnomes,goblins--sprites and fairy beings Hades,pluto, Arawn, Hela,Gwyn--underworld gods
8 Answers · Society & Culture · 17/10/2007