When the Spring Forward update landed on 31 March 2025, the Fever Case opened alongside it—and knife | Doppler (internal id am_sapphire_marbleized, finish #416) entered the drop table. It sits at legendary rarity with multicolor anodized finishing and a wear window of 0.00–0.08, one of the tightest bands on a knife skin. In practice that means Factory New looks dominate; Battle-Scarred barely exists, so most listings read like showroom pieces rather than beaters. Valve handled the design in-house, continuing the official Doppler marble/chrome lane for players who want something you can stare at in inspect and still equip when you push close angles.

The in-game flavor line warns that getting fooled by the soft look has serious consequences—and that tone fits. Valve’s description frames it as black and silver metal paint mimicking marble, wrapped in a candy-coat sheen. In inspect, grain and glaze shift with camera angle; on swings, the black–white contrast tracks the arc and reads louder than static screenshots suggest. It is pretty, but in tight spaces it still broadcasts status the way top-tier knife finishes do.

Release date

31 March 2025, Spring Forward update, released together with the Fever Case.

Designer

Valve—first-party work with no third-party creator credit; treat live wear rules and pattern behavior as the source of truth.

Which case

Fever Case. Unboxing remains the main route to a raw drop; finished knives trade on the Steam Community Market and on C5GAME, where comparing case cost against completed knife pricing before you commit usually saves regret.

Skin profile

• Weapon: knife
• Finish: Doppler
• Rarity: legendary
• Style: multicolor anodized
• Wear: 0.00–0.08

Black–silver marble grain plus glossy highlights; with max wear capped at 0.08, most of the variance lives in the lowest float band—brightness and how the marble lines sit—not in heavy scuff tiers.

What to watch for

Always inspect in-game before you buy: Doppler pattern placement varies by template, so two knives at the same wear can show different marble flow. The narrow float window makes chasing texture more practical than hunting “better Battle-Scarred.” As the sapphire-marble Doppler tied to the 2025 spring Fever Case, it carries both seasonal context and display value; pairing it with gloves or rifles in the same cool palette is straightforward. When you trade, match the display name knife | Doppler to the internal name am_sapphire_marbleized so you do not mix it up with other phases in the Doppler family.