Quick History

Even as a minigame in The Witcher 3: Wild Hunt, Gwent had "weather" cards with familiar names: Biting Frost, Impenetrable Fog, Skellige Storm, and Torrential Rain. The transition to standalone Gwent changed these cards' abilities considerably, yet they proved strong early on, so strong that players referred to a "weather meta" and CD Projekt Red even called the June 2017 update the "Weather Update."

The December 2017 "Midwinter Update" expanded the range of cards and effects that could affect one or more rows. Negative effects became "hazards," a broad name that not only included weather-themed effects but more mundane elements such as Pit Trap. The Midwinter Update also added row effects that were positive instead of negative, called "boons."

Why Play Boons and Hazards?

All boons and hazards are tools for long rounds, whatever their nature:

• They depend on the opponent having many units on a single row (Dragon's Dream, Pit Trap, Full Moon)
• They add or take away points each turn (the boons, the weather hazards)

Short rounds render boons and hazards ineffective. A Biting Frost, for example, is utterly useless if it's the only card in a player's hand in Round 3. Yet the same card, used at the start of a long Round 3, can accumulate upwards of 20 points of value. While the many-unit hazards want to be played late, the per-turn hazards and boons want to be played early to maximize their potential point value.

Boons

After the Midwinter Update and as of this writing, there are only two boons in Gwent:

• Golden Froth, produced by its namesake card and Ale of the Ancestors
• Full Moon, one of two tokens created by Moonlight

While Golden Froth theoretically provides two passive points per turn, this requires two units on the row affected by Golden Froth. Further, points are applied at random, making it difficult to predict the exact point values of various units; a bad roll could put multiple units at risk of being destroyed by Geralt: Igni, for example. While a handful of largely Scoia'tael synergies exist with Golden Froth (Mahakam Marauder, Farseer), the strategy is less powerful than other Scoia'tael options and thus sees little play.

Now compare Moonlight. Not only is the Full Moon aspect less demanding, requiring only a Vampire or Beast on the row rather than two units, Full Moon specifically interacts with Werewolf and Alpha Werewolf, and the powerful synergies create the backbone for the Moonlight deck in the Monsters faction.

Of course, Full Moon is only one side of Moonlight. The other option is the Blood Moon hazard, and while Blood Moon is less commonly used than Full Moon, its simple existence as a backup plan adds to its worth when building decks.

A final, underrated element of both boons is their ability to clear hazards. Only one boon/hazard effect can be on a row at any time, and new effects overwrite old ones. While dedicated hazard-clearing cards such as Archgriffin can be too narrow for certain metagames, boons will always hold value. Of course, boons in turn can be overwritten by hazards, and matches between Moonlight and Axemen or another Moonlight deck can see multiple cards cast in a fight over whether a boon or hazard will have the "last say" on a row.

Elements of Hazards

Gwent's existing hazard cards have several dimensions affecting their playability:

• Number of rows affected. All current bronze hazard cards affect only one row, while gold "pure hazard" cards Korathi Heatwave and Ragh Nar Roog affect all three.
• When they deal damage. This is the "many unit" / "per turn" split mentioned above. Dragon's Dream triggers for damage when its caster casts another special card. Pit Trap and Blood Moon deal their damage when applied and whenever another unit enters the affected row. All other hazards apply damage according to their rules at the start of each subsequent opponent turn.
• Quantity of damage. Two is the most usual number, either concentrated on a single unit or split. Pit Trap (three) and Dragon's Dream and Skellige Storm (four) are notable exceptions.
• Predictability of damage. Gwent players as a whole like effects they can predict and control. Pit Trap deals three damage to every unit, every time, with only armor affecting the possible points. Impenetrable Fog always hits the highest unit on the row, though ties are broken randomly. Torrential Rain's targets are inherently unpredictable.
• Interaction. While Drowner theoretically interacts with all hazards, no cards specifically interact with Torrential Rain, for example. By contrast, Foglet adds points and thins the deck by a card when Impenetrable Fog goes on an enemy row, giving an incentive to spawn Impenetrable Fog rather than Torrential Rain with Dagon.

Many-Unit Hazards

Dragon's Dream sees minimal competitive play. It does nothing on its own, requiring another special card to trigger, and the Gwent community consensus is that the card's effects do not justify its requirements. Pit Trap makes slightly more frequent appearances, mostly in Scoia'tael Movement decks, while Blood Moon, as mentioned above, generally is the backup option in Moonlight decks.

While many-unit hazard cards do not see much play as a group, they do affect a surprising number of games, thanks to Shupe's Day Off. One of the five possibilities for Shupe: Mage is to apply random hazards to all enemy rows, and in the final turn of Gwent Open #6, proNEO3001, facing a huge point deficit, found his best chance of victory lay in those hazards.

The siege row came up Pit Trap, dealing a whopping fifteen points. While the melee-row Impenetrable Fog and ranged-row Biting Frost proved unimpressive, only dealing two points each and causing proNEO3001 to come up short, changing either to a Pit Trap or Blood Moon would have won proNEO3001 the game, match, and title.

Per-Turn Hazards

The per-turn hazards, the weather-themed "classics" of Gwent, fall into four broad categories based on how they deal damage within their row(s):

• To the lowest unit. In this category are bronze card Biting Frost and cards that apply the effect; silver card White Frost, which applies Biting Frost to two adjacent rows; and gold card Korathi Heatwave, which does not count as Biting Frost but works similarly on all three rows.

By always affecting the lowest unit, this category of hazard can and will take units off the board by attacking them turn after turn with damage. On the other hand, this category will often "waste" points of damage by killing a one-point unit, thereby dealing only one damage per row and not the maximum of two, though cards such as Bloody Baron can make up for this seeming waste.

Biting Frost appears most frequently in Wild Hunt decks, thanks to its ready interactions with Wild Hunt Hound among other cards. Korathi Heatwave appears most frequently in weather-heavy Axemen decks.

• To the highest unit. In this category are bronze card Impenetrable Fog and cards that apply the effect, plus gold card Ragh Nar Roog, which does not count as Impenetrable Fog but works similarly on all three rows.

By always affecting the highest unit, this category of hazard trades more consistent maximum damage for seldom taking units off the board.

Impenetrable Fog appears most frequently in Deathwish, Moonlight, and other Dagon-based decks, as the combined points of Dagon and Foglet plus the two-damage-a-turn Impenetrable Fog adds up to a strong proactive play. Ragh Nar Roog, like Korathi Heatwave, is commonest in weather-heavy Axemen.

• By position. For now only Skellige Storm fits this category, which deals damage based on unit position. Skellige Storm deals up to four points of damage to up to three units: two to the leftmost, one to the second-left unit, and one to the third-left unit.

By always affecting the leftmost unit(s), Skellige Storm will sometimes "waste" damage on the leftmost unit, and the requirement for three units on the row for maximum damage can lead to inefficiency. On the other hand, when set up properly, Skellige Storm's four points per turn will add up quickly in a long round.

Skellige Storm is most common in weather-heavy Axemen, where the multiple units damaged can provide up to a triple trigger for Tuirseach Axeman and Derran.

• At random. For now only Torrential Rain fits this category, dealing one damage to up to two random units on a single row.

Torrential Rain sees little competitive play for a number of reasons. While it can deal up to two damage per turn to a single row, it requires two units on that row for maximum efficiency, unlike Impenetrable Fog or Biting Frost. The random damage means players cannot predict where damage will go, unlike with all other hazards. Finally, no cards specifically interact with Torrential Rain; there is no rain-themed equivalent to Foglet, for instance.

More demanding, less predictable, and less synergistic than its peers, Torrential Rain is the Golden Froth of hazards. Perhaps Homecoming will give it some new applications, but for now, competitive players largely leave it out of decks.