The latest Deadmines expansion for Hearthstone brought new PvE content and cards to Mercenaries and the one causing the most ruckus in ranked play has got to be Cookie, the Cook. Cookie has a lot of good traits going for him, including nature spells that synergize with already top-tier Mercenaries compositions and a supportive caster skillset that can fit in many different compositions.

Cookie, the Cook (rare caster) 

Type: Murloc
Stats at max level: 6/70

Abilities:

Fish Feast 5 (Nature): Speed 2. Deal 10 damage to an enemy. Deathblow: Give +15 Health to all friendly characters.

Cookie’s Cooking 5 (Nature): Speed 5, Cooldown 1. Bleed (5) to all enemies. Restore 5 Health to friendly Murlocs and Pirates.

Go Fish! 5 (Nature): Speed 4, Cooldown 1. Summon a random fish for your opponent, with a Deathrattle that benefits you.

Equipment:

Seasoned Pan 4: Fish Feast gives +5 Attack as well.

Iron Ladel 4: Cookie’s Cooking restores an additional 5 Health.

Appetizers 4: Start of Game: Give friendly characters +9 Health.

While the Murloc and Pirate synergy is no doubt useful in those compositions, Cookie value in the current meta is most felt via the Appetizers equipment, and his third ability unlocked at level 15, Go Fish!

Appetizers' +9 health buff happen at the start of the game, even if Cookie is not in your starting line-up. This passive survival bonus helps defend against common focus fire strategies that rely on a turn 1-2 Mercenary kill and additionally allows squads to better protect win conditions Mercenaries. It is especially useful in mirror match scenarios where the additional HP matters greatly.

Go Fish! summons an 0/15 fish for your opponent and, when it dies, something bad happens to the opponent. There are three possible death rattles, one heals friendly mercs, one gives friendly mercs bonus attack, and one deals damage to enemy Mercenaries. 

In some situations, Go Fish! can create value trades similar to Tavish (fighter) and his traps. The delayed value fishes' deathrattle gives Cookie a strong option on turns where additional damage or healing is not needed.

Another useful quality of this ability is that summons an additional unit on the side of your opponent. This synergizes well with "for each enemy" abilities, especially alongside a well-timed Earth stomp to Fire Stomp combo. Just when we didn't think Diablo could get any more deadly, he also turns out to be one of the most effective ways to kill Go Fish! summons and triggers the positive death rattle.

Other powerful strategies with Cookie involve Malfurion (protector) and/or Bruk'an (caster). The BBF nature pairing has enough speed manipulating abilities needed to land the occasional 0 speed Fish Feast Deathblow, while extra nature spell damage benefits Cookies AoE bleed damage. 

Liferoot Staff 4, the Malfurion equipment that causes friendly nature spells to heal 6 to all allied characters is a no-brainer with Cookie, as his three nature abilities ensure max passive value. It should also be noted that healing strategies get better the more max HP your mercenaries have – thanks Appetizers 4!

Go Fish! can backfire against enemy Sylvanas (fighter), as each friendly unit that dies further empower Reclaimed Souls Anti synergy. This can also happen with Diablo's Black Soulstone equipment, so fish responsibly.

Cookie in action

TeamAmerica, a competitive Mercenaries streamer that frequently holds the Rank 1 PvP spot has been playing with a Cookie composition on stream. In the clips below, Cookie + Diablo secures a kill thanks to an empowered Fire Stomp. Without Cookie, Stomp would have only triggered twice.

In this clip, Cookie scrapes a late-game victory. Many Mercenaries could have won in this situation, but would TeamAmerica's have survived this long if each of his Mercenaries didn't have bonus +9 HP throughout the game?

For every additional Murloc or Pirate that gets released, Cookie becomes a better Mercenary. The same can be said for new Mercenaries that care about # of enemy units, so in the long run, Cookie seems like a solid Mercenary to max out, especially in the current Diablo-filled meta.