I ask myself this question, because I am thinking about making an all-minion deck. “Best” will be a little subjective, for certain. Perhaps we can quantify this by looking at what kind of diversity or support they can bring to other cards.
Hunter- Has a great synergy with Beasts. There are a lot of beasts in the pool of neutral cards as well. I have a deck made for the “play 30 minions that cost 2 or less” quest. It’s a really fun deck that catches people by surprise but can easily be thwarted if the cards come out wrong.
Druid- They don’t have a lot of minions in their deck, but the ones they have are very powerful. Druid of the Claw is a good example. A 4/4 minion for 5 mana that can either have charge or 4 extra health and Taunt. Not too shabby!
Priest- Might have the most annoying minions. Everyone loves it when a priest pulls out a Northshire Cleric right? I have had some opponents fireball them! A little overkill in my opinion but to each their own.
Rogue- Has one of my favorites in the SI:7 Agent, a 3/3 minion for 3 mana that has a 2 point damage combo that can be use on a minion or player. That’s a solid and versatile card. Shame I only have one of them, but I try to put a couple Youthful Brewmasters in my deck to use it more than once ;) I am a tricksy rogue!
Shaman- A nice balance between versatility and power. I’m missing a couple cards from really being able to take full advantage.
Warlock- Has a lot of minions which are all demons, fittingly, which works with the spells in their deck. However, a lot of them have negative side effects. If just playing a strict minion deck, I’m not sure it would have the flexibility to counter those effects.
Warriors- Might have some of the most fun minions. One of my favorites is the Kor’kron Elite, which leaps into battle with a charge. A 4/3 minion that only costs 4 mana to play. Quite powerful.
I think my choices will come down to hunter, priest and shaman. I might just have to try all three. What class do you feel has “the best” minions? Feel free to let me know in the comments down below!