This seems to have largely flown under the radar, but yesterday WotC gave us a list of cards which are going to be added to Magic Arena a week from now for the Historic format. The cards are:

It’s easy to see what they are going for here. At least in many cases. I don’t really know about the [scryfall]Hidetsugu’s Second Rite[/scryfall], but you can see what they are trying to enable here (although I wish they would stop the artifact shenanigans, finally).

Let’s start with Goblins. We have some excellent combo pieces available to us already, but adding [scryfall]Goblin Matron[/scryfall] gives the deck consistency (which I wish they would stop doing as well).

[deck]
[creatures]
4 Skirk Prospector
4 Fanatical Firebrand
4 Tin-Street Dodger
4 Goblin Instigator
4 Ember Hauler
4 Goblin Matron
4 Goblin Warchief
4 Goblin Ringleader
3 Siege-Gang Commander
[/creatures]
[spells]
2 Banefire
[/spells]
[lands]
20 Mountain
3 Castle Embereth
[/lands]
[/deck]

This could be built quite differently, as we have plenty of interesting cards at three mana, but to keep the curve low, this is what I was thinking.

Hey, we also get [scryfall]Cryptbreaker[/scryfall] which feels like a basis for a Zombie deck to me.

[deck]
[creatures]
4 Cryptbreaker
4 Diregraf Ghoul
4 Lazotep Reaver
4 Graveyard Marshal
2 Eternal Taskmaster
4 Rotting Regisaur
4 Death Baron
4 Midnight Reaper
[/creatures]
[spells]
4 Liliana, Untouched by Death
4 Dreadhorde Invasion
[/spells]
[lands]
19 Swamp
3 Castle Lochtwain
[/lands]
[/deck]

A little less obvious addition is [scryfall]Distant Melody[/scryfall]. I don’t Elementals need help like this, but maybe Merfolk do.

[deck]
[creatures]
4 Benthic Biomancer
4 Deeproot Elite
4 Merfolk Mistbinder
4 Merfolk Trickster
3 Merfolk Branchwalker
4 Silvergill Adept
1 Kopala, Warden of Waves
4 Kumena, Tyrant of Orazca
1 Zegana, Utopian Speaker
[/creatures]
[spells]
3 Distant Melody
4 Spell Pierce
1 Sleep
[/spells]
[lands]
2 Temple of Mystery
4 Hinterland Harbor
4 Breeding Pool
4 Unclaimed Territory
3 Forest
6 Island
[/lands]
[/deck]

You have to be careful with the manabase here, as [scryfall]Temple of Mystery[/scryfall] and [scryfall]Hinterland Harbor[/scryfall] are not friends.

Knight are pretty strong right now, so perhaps there’s something there as well.

[deck]
[creatures]
4 Fervent Champion
4 Dauntless Bodyguard
4 Blacklance Paragon
4 Knight of Grace
4 Knight of Malice
4 Inspiring Veteran
4 Rimrock Knight
4 Acclaimed Contender
[/creatures]
[spells]
3 Steelclaw Lance
4 Embercleave
[/spells]
[lands]
4 Tournament Grounds
4 Unclaimed Territory
4 Blood Crypt
4 Godless Shrine
4 Sacred Foundry
1 Mountain
[/lands]
[/deck]

The manabase is… awkward. Maybe cut a color?