Hearthstone Battlegrounds is getting a fresh set of balance changes in Patch 27.4.2 which brings in a variety of different changes including buffs, nerfs, and pool adjustments. 

Quote From Blizzard

Anomaly System Update

Each week’s new Anomalies will now have a slightly smaller appearance bonus in higher-rated lobbies (they will still have an appearance bonus for the first week they are added compared to all the other Anomalies, but not as large of one). Lower-rated lobbies will still have the same offering bonus as before.

Anomalies Updates

Big League

  • Old: Only Tavern Tiers 3, 4, 5, and 6 exist.
  • New: Only Tavern Tiers 3, 4, 5, and 6 exist. Start with 10 extra Armor.
  • Dev Comment: Also, Demons are now banned from this Anomaly.

Everything’s On Fire

  • Old: At the start of the game, take 30 damage. After another hero dies, regain 5 Health.
  • New: At the start of the game, take 25 damage. After another hero dies, regain 5 Health.

A Faire Reward (the Triple Reward)

  • Old: Discover a Darkmoon Prize.
  • New: Discover a Tier __ Darkmoon Prize.
  • Dev Comment: Darkmoon Prizes are now locked based on the Tier you were at when you tripled, instead of giving a Prize based on the Tier you’re at when you play them.

Yogg-iseum

  • Old: At the start of each turn, all heroes spin the Wheel of Yogg-Saron.
  • New: At the start of each turn, all heroes spin the SAME Wheel of Yogg-Saron.
  • Dev Comment: This is a text-only wording update for clarity.

Golganneth’s Tempest

  • The following heroes are now banned from games with this Anomaly: A.F.Kay, Captain Eudora, Dinotamer Brann, Elise Starseeker, Forest Warden Omu, Fungalmancer Flurgl, Galakrond, Kurtrus Ashfallen, Ozumat, Scabbs Cutterbutter, Silas Darkmoon, Overlord Saurfang, Professor Putricide, Xyrella, Yogg-Saron, and Y’Shaarj.
Minion Updates

Imposing Percussionist

  • Old: [Tier 5] 6 Attack, 6 Health
  • New: [Tier 4] 4 Attack, 4 Health

Shady Aristocrat (Sire Denathrius's Buddy)

  • Old: [Tier 2] 2 Attack, 2 Health
  • New: [Tier 3] 3 Attack, 3 Health

Piloted Whirl-o-Tron (Sneed’s Buddy)

  • Old: [Tier 3] 4 Attack, 3 Health. Battlecry: Copy a different friendly minion’s Deathrattles.
  • New: [Tier 5] 5 Attack, 4 Health. Start of Combat: Copy all other minions’ Deathrattles (except Piloted Whirl-o-Tron).
  • Dev Comment: Yes, ALL. With this update, Piloted Whirl-o-Tron has been returned to the “Bring in the Buddies” Anomaly’s Buddy pool.

Street Magician (The Great Akazamzarak’s Buddy)

  • Old: 5 Attack, 3 Health. Deathrattle: Put a random Secret into the Battlefield.
  • New: 3 Attack, 5 Health. At the end of your turn, cast a random Secret.
Minion Pool Updates
  • Keyboard Igniter and Spark-ling have been removed from the minion pool.
  • Felemental has been returned to the minion pool.

More Balance Changes

If you're looking for other balance changes, we've got them all covered in dedicated articles based on the format.

Additionally, Hearthstone Battlegrounds is set to receive a few changes in the update and Duels also gets some love.