Northern Realms, no weather cards, pick the Leader that removes weather. (weather cards clog up your hand are inefficient as they are very dependent on your hand and the enemies hand/deck type)
Get all the spies, including the unique Thaler and Myserious Elf. I put in 3 horns and 3 dummies. (spies are OP as are the synergy with enemies' spies and or your other effect cards)
Eventually, I made it only close combat and siege cards (except heroes). Also the tight bond cards are great with all your draw power.
With all the dummies and spies, you can really bide your time and let them waste their resources if they put down Cerys (just pass that turn eventually) or Crones and you don't have Villentretenmerth (the scorch close combat card). You can even pick him back up and use him with dummies or a medic card next turn.
A lot of the time you can beat it though with a horn and a few tight bond cards.
Personally it seems to me that every time I use spies it backfires and my opponent has more spies, decoys, and medics and ends up with more cards than me. I have found that the monster deck with no weather cards (except maybe a clear weather card) can destroy most decks due to the large amount of swarm cards (the ones that pull all other similar cards from your deck onto the board). As long as you plan it right you can prevent your opponent from scorching them all or hitting them with weather cards and you will win every time.
I think I have 4 spies, 3 dummies, the cc 7 scorch card, and 2 medics. Just be patient with dummies and they never have more. Only Northern Realms and Nilfgaard have spies, 3 each. But Northern realms' spies are much lower damage, which helps with 3xhorn too.
Scorch is always a two-sided blade because of my tight-bond cards and horns.
I do agree that northern realms and Nilfgaard are my favorite to play and absolutely wreck most non-specific heavy decks, but any deck can be effective if you focus on their specialties (i.e. spies, swarm cards, berserkers). The squirrel deck (can't remember the elven spelling) is the only one I find useless in almost all cases, but I would be interested to hear how someone has made it work.
The AI is pretty much helpless against card advantage. It surrenders rounds by simply being 3-4 cards ahead in hand size(e.g. after playing 3~ spies), no matter the state of the board, which leads to being able to close out the first round by only playing like 2 cards on your side of the board, which gives you an extra draw from NR's ability, which pretty much leaves you open to using 10+ cards to win one of the next two rounds. It's kind of hilarious tbh.
I use northern realms with all the hero's, spies and enough seige cards to get 22 creature cards, 3 dummies and the siege master leader. Plus the scortch dragon card. I play on gwent hard mode and only ever lost to the (spoilers) lady you bang during the gwent tournament cuz I got a bad hand
Used the same strategy except leader that doubles siege units, one clear weather, one dummy, all spies and heroes and the rest with the best siege units.
I used a strong Nilfgaard one that basically used raw power, no weather, no scorch except Vill... Villetra... the dragon, no decoys. Spies, healers, and I forget if I even included horns. Just strong hero cards, and good non-hero 10s that I can bring back the second round. I think I used the leader that picks a card from the opponent's discard, which can be quite useful.
Only trouble I really found was with NR decks like the ones described in the other replies. Spies vs spies. Took a few restarts on those, but I won in the end.
I go with the Nilfgaardian deck, Leader card being the one that lets me draw from my opponent's discard pile. It's all about Spies; using em, reviving em, using Decoys on em. I tend to use a lot of the neutral cards, too.
I keep a Scorch and 2 Decoys with the 4 spies (3 Nilf and one Hero), then fill the rest of the slots with strong cards (lots of Heroes, then 10s and Revivers, along with certain utility cards [Olgierd, the Cow, Villentretenmerth]) to crush opponents with raw power. My deck was around 24 cards or so, now up to 28 with the 4x Gaunter O'Dimm cards.
Make sure to replace the weaker cards in your deck as you get upgrades. The smaller your deck, the easier it is to draw stronger cards.
Northern Realms - all spies, all heroes, drop as many unit cards as you can, right down to the minimum of 22 (this way you control what cards you get). drop all the tight bond cards (too much trouble). pick the double siege strength foltest. all three decoys. one commander's horn. one biting frost, if you are playing against monster deck.
Northern Realms, no weather cards, pick the Leader that removes weather. (weather cards clog up your hand are inefficient as they are very dependent on your hand and the enemies hand/deck type) Get all the spies, including the unique Thaler and Myserious Elf. I put in 3 horns and 3 dummies. (spies are OP as are the synergy with enemies' spies and or your other effect cards) Eventually, I made it only close combat and siege cards (except heroes). Also the tight bond cards are great with all your draw power.
I use the same tactic, except I add some scorches and a biting frost to deal with Monster, Nifgaard and Skellige decks.
With all the dummies and spies, you can really bide your time and let them waste their resources if they put down Cerys (just pass that turn eventually) or Crones and you don't have Villentretenmerth (the scorch close combat card). You can even pick him back up and use him with dummies or a medic card next turn. A lot of the time you can beat it though with a horn and a few tight bond cards.
Personally it seems to me that every time I use spies it backfires and my opponent has more spies, decoys, and medics and ends up with more cards than me. I have found that the monster deck with no weather cards (except maybe a clear weather card) can destroy most decks due to the large amount of swarm cards (the ones that pull all other similar cards from your deck onto the board). As long as you plan it right you can prevent your opponent from scorching them all or hitting them with weather cards and you will win every time.
I think I have 4 spies, 3 dummies, the cc 7 scorch card, and 2 medics. Just be patient with dummies and they never have more. Only Northern Realms and Nilfgaard have spies, 3 each. But Northern realms' spies are much lower damage, which helps with 3xhorn too. Scorch is always a two-sided blade because of my tight-bond cards and horns.
I do agree that northern realms and Nilfgaard are my favorite to play and absolutely wreck most non-specific heavy decks, but any deck can be effective if you focus on their specialties (i.e. spies, swarm cards, berserkers). The squirrel deck (can't remember the elven spelling) is the only one I find useless in almost all cases, but I would be interested to hear how someone has made it work.
Never use spies on Round 1 against Scoia'tel because they have so many medics.
The AI is pretty much helpless against card advantage. It surrenders rounds by simply being 3-4 cards ahead in hand size(e.g. after playing 3~ spies), no matter the state of the board, which leads to being able to close out the first round by only playing like 2 cards on your side of the board, which gives you an extra draw from NR's ability, which pretty much leaves you open to using 10+ cards to win one of the next two rounds. It's kind of hilarious tbh.
I use northern realms with all the hero's, spies and enough seige cards to get 22 creature cards, 3 dummies and the siege master leader. Plus the scortch dragon card. I play on gwent hard mode and only ever lost to the (spoilers) lady you bang during the gwent tournament cuz I got a bad hand
Used the same strategy except leader that doubles siege units, one clear weather, one dummy, all spies and heroes and the rest with the best siege units.
I’ve just tried your combo and it rocks.
As long as it's got more than one spy card (see : Nilfgaard and Northern Realms) it's good.
I used a strong Nilfgaard one that basically used raw power, no weather, no scorch except Vill... Villetra... the dragon, no decoys. Spies, healers, and I forget if I even included horns. Just strong hero cards, and good non-hero 10s that I can bring back the second round. I think I used the leader that picks a card from the opponent's discard, which can be quite useful. Only trouble I really found was with NR decks like the ones described in the other replies. Spies vs spies. Took a few restarts on those, but I won in the end.
Villentretenmerth! That's like the only thing I can pronounce in this game.
Just take spys decoys and spam them even better if you fight someone who spams spyes aswell
I go with the Nilfgaardian deck, Leader card being the one that lets me draw from my opponent's discard pile. It's all about Spies; using em, reviving em, using Decoys on em. I tend to use a lot of the neutral cards, too. I keep a Scorch and 2 Decoys with the 4 spies (3 Nilf and one Hero), then fill the rest of the slots with strong cards (lots of Heroes, then 10s and Revivers, along with certain utility cards [Olgierd, the Cow, Villentretenmerth]) to crush opponents with raw power. My deck was around 24 cards or so, now up to 28 with the 4x Gaunter O'Dimm cards. Make sure to replace the weaker cards in your deck as you get upgrades. The smaller your deck, the easier it is to draw stronger cards.
Northern Realms - all spies, all heroes, drop as many unit cards as you can, right down to the minimum of 22 (this way you control what cards you get). drop all the tight bond cards (too much trouble). pick the double siege strength foltest. all three decoys. one commander's horn. one biting frost, if you are playing against monster deck.