And both of these cards fits perfect for what an arena deck usually lacks.
Death's bite - new weapon and Warrior's biggest issue in arena is not
getting any weapon simply getting 1 more decent weapon increases the
total chance and makes it easier playing Warrior. Now this weapon is
pretty good too.
Death's Bite can trigger Enrage which warrior is know to pick. That's great in Constructed, fits perfect with cards like Acolyte of Pain and Armor Smith. Not so common in arena to get an Armor smith0. But Raging Worgen, Amani Berserker etc all those cards have always been extra good picks for a warrior so this card fits very good into the overall warrior arena prioritize picks.
But if anything why it is so good is because it fits the void warrior had at 3-4 mana cost weapon and ---- It does 5 damage. IF there is anything that really lifts it up. Its that the second attack will do 5 damage to the minion you attack. This makes it be really strong at the medium range cost, play it turn 4 kill a turn 3 drop. Opponent drops (opponent turn 4) Yeti - Kill it.
What this leads to its that a warrior with a good start is ridiculous strong right now. If the warrior can use fiery war axe turn 2 and then Death's Bite. HUGE tempo. Even worse if the warrior can drop a Frothing Berserker in between at turn 3.
Its a very good pick for warrior. I would not pick it over Fiery War Axe as that card takes the early game so hard. But after that this card is the best. As it likewise taht the early-mid game easily. Its a lot better then Arcanite Reaper, it cost makes it less of a tempo / board adcantage card and more of a Finisher and the Death's bite as mentioned second attack do deal 5 damage so for 1 more mana to deal 1 more damage.
Death's Bite will sometimes backfire and injure something you control but as that can also be and advantage its a lot of a gray zone if that ability is good or bad looking at the overall board. The biggest issue and what one should think about its vs Mage/Rouge/Druid who might get a chance to kill a 3.2 (becoming a 3.1) after the weapon is used.
Dark Cultist like Death's Bite fits amazing for the priest weakness. Priest has problems with early board presence and this card literately got the best 3 mana drop stats. Its alone being a 3.4 for 3 mana.
At first there was images from Blizzard showing it as a 2.4 which it would still be a good card for priest. Just like even an unbuffed Unbound Elemental can get good trades of its 4 life.
So this card got high life, makes it be able to trade with almost any 2-3 drops and survive + its on priest so healing it will make it life longer. Then it got 3 attack....so it can kill any 3-2 drops And on top of that it got a Deathrattle effect which is pretty good.
This card would be amazing even just as a 3.4 no abilities. Would be the Yeti of 3 drops. But only for priest. Obviously its a super high value card. Even if people play around it to not trigger its Deathrattle its still just a huge pain in the ass as it will almost always trade up.
And the Deathrattle is great for overall priest, increasing the life for more heals, easier trades and so on. But were it really shines if its followed by an Auchenai Soulpriest drop turn 4, kill it of to get a 3.8 Soulpriest. As you cant heal her she has always been very solid to combo with + life.
What is it to be said about this card? Not much its a very fun card in Constructed I am playing Mage Secret deck right now but its almost 100% useless in Arena. 2.2 for 2 its really bad. Its essentially just playing a Secret for 2, which you cant pick what secret it is. Well as its Arena you likely just got 1 secret so arguably you can. Its not horrible in Arena if you got the right Secrets for it but other wise its a huge Tempo loss. And Paladin secrets are just not worth the time to pick them....so it don't fit in there. Some mages secret do nothing in arena like Ice Armor and Vaporize will likely get a 1.1. For Hunter explosive Trap can be good and it can also do nothing. Well if the this 2.2 trades with a 2.3 and gets out a Explosive Trap that could mean it dies of it...but that would mean you need not play out any minion so the opponent cant trade it.
The overall issue is that what Secrets are picked in Arena? Noble Sacrifice its a Paladin, Explosive and sometimes Frozen if Hunter. Mage Mirror or Counterspell. That's pretty much it. There is not a lot of guessing game ( well I guess duplicate is popular now to). Mad Scientist works great for a control Mage in constructed were its a bunch of different secrets and the mage can regain board control with a lot of different stuff + can win late game with cards like Archmage Antonidas.
Without the guessing game this card don't do much. And its absouly not worth picking bad arean secrets to make one card more valueable.
Of course its possible to get a heavy secret deck for mage primarily but the chance of that is slim to none.
Undertaker is a really good card in constructed I would go so far and say overpowered. A 1.2 that grows for pretty much all minions you play in a deck centered around the mechanic.
Its a decent card in arena actually, just playing 1 more Deahtrattle with it means its a 2.3 for the price of 1 mana. If its silenced thats just great, losing 1.1 stats on one minion for a silence even 2.2 can be better then losing a real buff card etc. But obviously one can't do a deck and only have 1 Deathrattle and hope to get them on the same time. So its not that its amazing but if you have like 4-5 Deathrattle in the deck its not the worst pick in the game.
The class that can use it the best is Warlock, making a zoodeck its the common practice for arena. It has 2 things going for it to be in Zoo, it cost 1 mana. So great with life tap and overall flooding the field. But also the Zoodeck should take a lot of the cheap early minions such as Haunted Creeper, Leper Gnome, Loot Hoarder etc. Which will mean that the overall chance of getting Deahtrattle is higher. For Warlock its not to bad to take Undertaker even when having no Deathrattle. However, that do require one thing. That is a lot of cheap minions. Its not good to jut take Undertaker pick 2 for a Warlock if the rest of the deck happens to go towards mid range or even late game control. Sometimes that is just the only viable options but at pick 10+ when its clear the deck is going to be a cheap ass aggro deck. This card is a great pick.
Shaman can also value this card higher for the simple reason that shaman can value Deathrattle cards in general high regard. But its not that Shaman can pick in i an a vacuum just that it likelier will be better for the Shaman and that having a few cards who synergies could still make it worth picking.
Warlock ++, Shaman +
Zombie Chow is really good in arena, a 2.3 for 1 its amazing and the drawback usually means nothing. Life is something a lot of people overvalue, life means almost nothing in arena as people cant get enough direct damage or what is usually called burn cards.
As that wont happen enough its not bad to have to heal the opponent, I guess the only class it will be bad is for Hunters. And possible mage who got huge number of fireballs etc. But even for that mage, the game likely will be won on board control and not on life.
As it cost 1 mana and got huge stat it naturally fits in Zoolock.
But clearly were it is the best is Priest. First of all awesome in priest constructed as it can be played as one of my favorite Yu-gi-oh decks: Bad Reaction to Simochi. Simochi turns around all heals on the opponent making it a lot better then A Soulpriest but still its clear that with Soulpriest out huge amount of damage can be dealt with this card and other heal cards.
While Soulpriest is not always available to be picked its the best rare for priest in the game and better then the epics as well. So one can at least assume there is the possibility the Deathrattle will be damage later on as priest.
But the biggest reason why its such a good priest card is because of time. The more turn you expect your average game to take, the less life is important. Priest being the obvious stall class who win late game clearly take the most turns on an average scale. Main reason why it work greats for priest. Similar Zombie Chow works for Paladin, who usually takes time on them and the same with Druid. For both Paladin and Druid it also adds an extra bonus of being bad to silence. Buff it with a Mark of the wild and like Ancient Watcher its slightly silence proof.
Priest +++, Warlock Druid Paladin ++. Shaman + Rogue +
IF we just ignore Wailing Soul's abilities and first look at this stats. It actually got pretty bad stats in away. Yes most people wil think I am crazy it got the same stats as Senjin. But Senjin really don't have so good stats either. In Hearthstone you want to follow the 2n+1 stat were N is the mana cost. So if a card cost 4 mana it should have 9 stats. They got 8 stats. Typical for a Taunter to have 1 less. So its not like Senjin is bad in a Taunter sense he also got the high health being a defense taunter and not an aggressive taunter like Booty Bay which is a really bad card. So all together Senjin is great. But its because he got the right medium stats with taunt. The other taunters later on like Fencreper got really bad stats and the others are attack oriented...
3.5 is still of course a lot better then 5.3 but I would say worse then 4.4 However, it all just shows how good Yeti is at 4.5
But what really makes Wailing Soul Bad, is that it got a bad ability. Even in constructed its hard building around it. There are some cute play like Equality and then playing it. That wont ever happen in Arena. In Arena you cant pick not to have minions who don't have ability. To play Wailing Soul its mainly as an anti Freeze mage or I guess is some kind of Vanilla/normal deck were one just focus on having good minions with no abilities (which don't really exist in Hearthstone maybe one day).
In arena, the deck will consist of really good cards like Harvest golem and other staple picks. Many of them will just be ruined by Wailing soul.
So decently bad stats and bad ability.
Stalagg --- What can I say. Its a terrible card anyone can figure that out. It do have 11 stats which is reasonable for a 5 drop ignoring its ability. Which one should as it absolutely never will happen in arena. The biggest chance if its happening if it the other player helps out dropping Feugen before hand...
Stalagg will die by pretty much removal. Frostbolt + fireblast. Swipe, wrath + shapeshift, Lightingbolt with spell damage or sac something small and so on. Its like a cheaper corehound.
Feugen on the other hand is a great card. Its like a big Yeti. + 2 more stats so good for its cost. 4.7 makes it really hard to remove and it can kill most stuff.
Really is the same in counstred as well. Stalag really feels like an appendix to Feugen, might as well play him to maybe get Thaddius. I would not be suprised in future top deck having just Feugen because hes a really solid 5 drop.
And thats what Feugen becomes in Arena, just a solid 5 drop. Better then many off putting arena picks with high RNG factor etc. But not the best, e.g Cairne is much better.
Priest ++. Druid + Paladin +