Blizzard is making several changes to Hearthstone with the upcoming 7.1 update, and we've learned of yet another area that will be undergoing some serious revision: Arena Mode. The changes include one major format change, and several smaller balance tweaks that should have a big impact on the mode.

Starting with the next game update, Arena will switch from Wild to Standard format. In an update, Blizzard said this is to help players have a greater degree of control over card synergies. Arena Mode lets players draft a deck by being presented with choices between three cards. As the card pool grows, the chances of drafting two or more cards that work well together gets less likely, so shifting to the more limited Standard mode will increase the odds of drafting a decent deck. Standard limits card choices to the last two seasons of expansions, plus Basic and Classic sets.

In addition to that, Blizzard will be changing the frequency of card distribution for your draft. Common cards were making up almost 80% of all the cards drafted, and so the team will be tapering that off and making Rare, Epic, and Legendary cards show up more often. Classic cards will also show up less frequently. Two particular common cards, Abyssal Enforcer and Flamestrike, will have their instances cut back severely, since they're powerful removal tools exclusive to their own classes.

Spells will also get a frequency boost in Arena drafts, since Blizzard says a lack of spells tends to reward whichever player can push minions out faster. Having more spells, and therefore more removal options, will make it easier to punish an opponent who's overextending. 

Finally, in some good news for long-time card collectors, golden cards will show up in Arena. It will be limited by the cards that are actually part of your collection, so if you have one golden copy, you only get a golden version for the first card. If you own two, however, every copy of that card in the draft will be golden. Arena is the only mode in Hearthstone that regularly allows you to hold more than two copies of any card.

All this comes in addition to already-announced ladder changes and nerfs to major staples within the Hearthstone meta. It's all due to come in an update in late February, so we can likely expect a release announcement soon.