First Impressions
The Storm Assassin Sword, released in December 2016 as an exclusive international release (primarily for the Asian market), comes in a dark, elegant "2-Tone Black Pearl" look. A special feature of this ball is the unusual combination of core and shell technology: inside works the legendary Centripetal Core, which gained worldwide fame through the Marvel series. In the 15-pound version, this symmetrical core delivers a low RG of 2.48 and a strong differential of 0.050. This high-performance core, however, is wrapped in the Reactor Pearl Reactive coverstock, a shell normally found in the entry-level class (Tropical series). With a factory 1500-grit polished finish and the "Lava Spice" scent, this ball aims to tame the explosive dynamics of the Marvel core with an extremely clean, low-friction cover.
Comparison
This specific construction makes the Assassin Sword one of a kind in the Storm lineup. Compared to the Storm Marvel Pearl, which uses the same core, the Assassin Sword offers considerably more length and a delayed reaction thanks to the Reactor cover. Where the Marvel Pearl still reads the midlane with its R2S shell, the Assassin Sword glides effortlessly over it. Compared to the Storm !Q Tour series (which often serves as the basis in the Sword line), the Assassin Sword differs fundamentally in the core: the Centripetal Core used here (0.050 diff) flares considerably more than the C3 core (0.029 diff) of the !Q Tour. It therefore creates more dynamics at the breakpoint than an !Q Tour, but needs drier conditions to grab. You could call it a "Super-Tropical": it offers the length of an entry-level ball, but the hit and pin action of a high-performance ball.
On the Lanes
The Storm Assassin Sword is an absolute specialty weapon for dry to medium lane conditions or for surfaces with extremely high friction (e.g. older wood lanes or worn synthetics). It is the ideal solution when even balls like the Hy-Road or !Q Tour start up too early or "burn up". Because of the Reactor shell, the ball almost completely ignores the first 40 feet of the lane and stores all of its rotational energy for the last few meters. That makes it perfect for "late block" scenarios in tournaments, when the heads and the midlane have dried up but you still need a ball that mixes the pins powerfully and does not — like many pure entry-level balls — suffer from deflection. It lets you play aggressively through the dry heads without having to worry about an early hook.