Hearthpwn

Even in Standard Aggro Hunter can probably get away with playing only beasts and spells. Just use Crackling Razormaw instead of Houndmaster.

But in Wild this card will become better and better with every expansion, as new beasts that fit the deck are printed.

Clarification from Peter Whalen they are not copies

To clarify - it’s taking the cards from your deck. It’s like Assembly in that you get 3 cards (or 1) but different in that they’re not generated, they move from deck to hand

https://twitter.com/LegendaryFerret/status/1066432943101378560

You build decks for cards like this.

Drawing three cards for three mana is a great deal, although making the all Beast deck needed to use this card means dropping Houndmaster.

Perhaps this could work in a moderately slow deck with a few powerful Beasts, so I'd have a guaranteed way to draw them.

3 mana, draw one minion card. But having more minions in your hand rather than discovering spells, pretty good.

So how exactly does this work? If you happen to hit three beasts, you draw all of them. If not, you only get one minion. But what happens to the other two cards? Are they burned? Is it like a 3 mana draw a minion burn two cards then? 

Also, what happens if you only have one or two minions? Could you use it to tutor, say, Subject 9 or something in an otherwise spell only deck? 

Quote from SuicidOr >>

So how exactly does this work? If you happen to hit three beasts, you draw all of them. If not, you only get one minion. But what happens to the other two cards? Are they burned? Is it like a 3 mana draw a minion burn two cards then? 

Also, what happens if you only have one or two minions? Could you use it to tutor, say, Subject 9 or something in an otherwise spell only deck? 

 This! This is why I think this card is so confusing.

What does it do exactly? Does it draw the cards form your deck or does it create extra copies? It doesn't say "discover a copy..." but all discover cards so far in hearthstone create copies of something, so this would be the first to actually draw them.

I know that cards like Shadow Visions and Stitched Tracker specifically say "a copy" but if we take a look at Drakonid Operative it doesn't, yet it creates a copy of a card. Cloning Device has pretty much the same effect and this one actually says "discover a copy..."

#Consistency

Discover something from a deck should always generate a new card, that would be consistency. If this card really draws from the deck then I think it's really poorly designed. If it creates extra copies then I think the wording is terrible, it should've been "keep them all" and not "draw them all".

Assuming that it draws from the deck (that's probably what it does) and you dont hit 3 beast I believe that you keep the card that you choose and the other two stay on your deck, they would only "burn" if the text said so.

If you only have one minion you will draw that minion. If you have two minions you have to choose one or the other, simple. So yes, you could use this as a tutor.

EDIT:

Ok, I just realised that has been confirmed that it is indeed a draw effect.
Poorly designed card it is then.

This card is absolutely insane in Barnes- Y'shaarj Hunter in wild because it actually DRAWS the discovered minion from your deck.

Turn 3 Master's Call -> Turn 4 Barnes 

This is a fun card. It satisfying as hell to get it off with Untamed Beastmaster on the board. Running a few non-Beasts as combo pieces kinda turns the downside into an upside as well.

They are out of their mind, aggro decks shoudn't have too much draw power otherwise it's too op, it doesn't STOP there, WTF, Rexxar and this? Like, wtf are they thinking, why they thought that it would be a good ideia to make an already powerful aggro transform into an very powerful control with only one card? Like, people that think that's okay are fucking crazy.