What does the deck do: The deck plays like a ramp/control or even midrange deck depending on the version and tries to get down doubling season + creatures/planeswalker resulting in insane value or straight up victory on the spot.

Win con/s: for doubling + planeswalkers right now on arena there's plenty of combos, i'm gonna mention 3 that I think either require the minimum amount of cards and/or close the game the fastest:

1) Jace, Cunning Castaway = infinite tokens

2) Jace, Cunning Castaway + Nicol Bolas, Dragon-God = infinite tokens, jace/nicol bolas copies (since bolas can use jace's loyalty abilities), with those nicol bolas copies we make the enemy sacrifice their board and then -8 to win instantly.

3) Ugin, the Spirit Dragon or Nicol Bolas, God-Pharaoh + Nicol Bolas, Dragon-God = instant win (not allways the case with ugin but very likely)

With that in mind at the moment she doubling season + walker shell probably looks something like:

3-4 doubling season

1-4 Jace, Cunning Castaway

1-3 samut, the tested maybe as under doubling season it acts as a planeswalker tutor that instantly wins us the game if we have combo number 2 or 3 in our deck and

1-2 Nicol Bolas, Dragon-God this would basically only really be played with jace and samut in the same deck to allow for a otk under doubling season but it could also otk on it's own very often, only negative is how hard it is to cast this card.

Ramp options:

1) green devotion tech: Nykthos, Shrine to Nyx + Kiora, Behemoth Beckoner + utopia sprawl and then manadorks or other ramp options of your choice, one cold even just build a standard green devotion shell to base this deck on.

2) Lotus field tech (discontinuity/stifle/strict proctor/blood moon).

3) gate deck ramp tech

draw options: the one ring/enchantress's presence(if the deck contains mostly enchants)/up the beanstalk(if the deck runs mostly 5+ cost spells)/kiora, behemoth beckoner(if creature based).

Defensive options:

Ramp/creature hybrid: If one opted to go for a green devotion shell one could just rely on big creatures for defence while waiting for the doubling season to come in while playing with nykthos kiora etc this could offer a stable defence line, good ramp and also a solid draw engine for the deck with kiora.

Gate: One could build this deck on a gate deck shell, beying able to use the ramp gate decks have through their sorceries/creatures and baldur's gate specially on top of beying able to use gates ablaze is quite nice.

Boardwipes: 4 - 8 of whatever you prefer, it wouldn't be bad to be in white to have the likes farewell/sunwell/divine purge/doomskar/Settle the Wreckage or red for the cheaper 3 cost brooderhood's end/anger of the gods or azorious for Supreme Verdict (uncounterable) but also black isn't bad with languish or blood on the snow to revive a walker (in case we run enough snow lands). Ultimately what you use depends on the colors the deck runs.

Fog Effects: haze of pollen, root snare, commencement of festivities, moonmist, teferi's protection, eerie interference, one ring (which we could play together with meticulous excavation for a 7 mana per turn infinite fog effect, on top of that mericulous excavation could be used to bounce our planeswalkers back if need be). This is definitly our cheapest option as most fog effects cost bethween 2 and 4 with the downside beying that this only buys you one more turn.

Weaknesses: aggro decks, combo decks, thoughtseize, removal and control decks in general can be tricky

Noteworthy Planeswalker options:

jace, cunning castaway: Infinite combo =doubling season on the field, cast jace, cunning castaway use the -5 jace makes "infinite" clones of itself and "infinite" creature tokens aswell, if nicol bolas, dragon-god is also played it allows for infinite copies of bolas aswell allowing us to also make the enemy discard and sacrifice all their permanents to the point we can use his -8 to instantly win the match.

tamiyo, field researcher: all usable abilities, her -7: draw 3 and omniscience emblem is insanely powerful synergizes very well with teferi, hero of dominaria

teferi, hero of dominaria: all usable abilities, his -8 is what we are here for, with all the draw this deck has in 2 or 3 turns we are likely to have exiled all major threats/lands the enemy has, synergizes very well with tamiyo, field researcher

Wrenn and Realmbreaker: great abilities, cheap, in color and amazing -7 NB: IF one had 2 mox ambers while having wrenn's emblem = infinite mana.

Wrenn and Seven: while the abilities aren't allways amazing and the casting cost might be too much, the +1 and 0 helps us ramp (although if we can cast this we likely don't need to ramp much anymore, the -3 makes for a amazing meatshield and the -8 is amazing if our graveyard is big

Tamiyo, compleated sage: usable kit, we probably care the most about her -x to pick back up doubling season OR another planeswalker from the graveyard, aside of that she isn't great, her -7 is neglectable

Ugin, the spirit dragon: all abilities are great (if using low level enchantments as ramp his -x might be detrimental to your own mana)

Nicol bolas, dragon-god: if his coloring/cost isn't a problem he should be played to some extent as all his abilities are great, combo with doubling season + jace, cunning castaway OR ugin, the spirit dragon OR Nicol Bolas, God-Pharaoh for a ista win.

Liliana, dreadhorde general: all her kit is usable and her -9 wins games

samut, the tested: -7 tutors for 2 creatures/walkers often resulting in a won match specially if under the effect of doubling season (in the case of planeswalkers for example: nicol, bolas, dragon-god + jace, cunning castaway or ugin, the spirit dragon. the other samut, the tested abilities are weak and not what we are after generally.

Nicol Bolas, God-Pharaoh: hes great although hes quite hard to cast on his own (samut can help with this), his whole kit is bonkers.

Valki, God of Lies/tibalt, cosmic impostor: if we are in color the modality offers us alot of options but it's tibalt's we are really after as his whole kit (specailly his -8) is amazing. (be aware that storm the festival will only allow us to cast valki).

nahiri, the harbinger: -8 tutors for any artifact/creature rest of her kit's also usable

kaya, the inexorable: her whole kit is good and her -7 allows you to tutor and play for free legendary, the negative is that this effect happens at the beginning of each of your upkeeps meaning she essentially does nothing when she lands on the battlefield IF used exclusively for her -7

Tasha, Unholy Archmage: great vs creature matchups because of her +1 but her -6 isn't allways great

Nissa, Who Shakes the World: her passive gives us mana, +1 is nice to chompblock, her -8 removes all the forests from your deck, the issue is her -8 by itself doesn't win you the game, her chompblocker is meh, because of her cost, her ramp come into play usually when you don't need it anymore and at this point you would have rather had some other planeswalker instead, specially with doubling season on the field.

Nissa, Vital Force: great kit + makes you realiably chompblockers, -3 makes you able to pick backup a boardwipe or like a doubling season you desperately need and her -6 makes your land drops not dead BUT she doesn't win you games and you would likely want another planeswalker to combo with doubling season

the rest of the walkers ain't on arena yet, are too expensive, are too off-color or feel like they would't achieve too much for a walker based deck (for creature centric doubling season decks there are some other synergistic planeswalkers of course).

Deck Variants:

-----------------------------------------------------------------------------------------------------------------------------------------------

 Enchantment Duplication: https://aetherhub.com/Deck/selesnya-enchantmentsdedicated-dollmak-970310

-----------------------------------------------------------------------------------------------------------------------------------------------

Doubling Season Walkers: https://aetherhub.com/Deck/h-doubling-season-walkers-958648

-----------------------------------------------------------------------------------------------------------------------------------------------

Doubling Season Green Devotion: https://aetherhub.com/Deck/doubling-season-green-devotion

-----------------------------------------------------------------------------------------------------------------------------------------------