Blizzard has benched the best assassin in its up-and-coming MOBA Heroes of the Storm, banning StarCraft star Zeratul from use in the game's first real round of professional tournaments for the indefinite future.
While Blizzard hasn't exactly confirmed this, the Zeratul ban sure seems like it stems from a bug of some sort that was recently discovered in a professional tournament that allowed the stealthy Protoss warrior to shoot across huge distances on a map with lightning speed — something he's not normally able to do.
The bug affects a special move called "Shadow Assault," one of the two powerful "heroic abilities" that Zeratul (like any HOTS character) can unlock once he reaches level 10 in a given match. When cast, the ability overclocks Zeratul for a few seconds — increasing his attack speed by 20% and making him leap forward to an enemy he's attacking. Zeratul is a stealth-based assassin who's supposed to duck in and out of combat and deal massive amounts of damage so quickly his enemies barely have time to react, let alone defend themselves, so Shadow Assault is a logical boost to his base performance. It helps him close the gap between himself and a target trying to flee from his deadly attacks, allowing him to relentlessly hound down enemy targets.
But only to a point. Like any ability in Heroes of the Storm, Shadow Assault isn't supposed to give Zeratul powers so super they risk breaking the game. Fans started to notice that the move was unlocking incredible feats last week, when a player for the Korean pro HOTS team MVP Black used Zeratul in some strange ways in a grand final tournament match against rival team Virtus.pro.
Instead of just making him jump forward short distances, MVP Black's Zeratul was zooming across the map. Players picked up on the oddity on Reddit, and discovered it could be triggered by changing Zeratul's target at the exact right moment mid-charge. Here's one demonstration video to give you an idea of what it looks like:
Many players were concerned to see Zeratul's heroic suddenly turn into something far more powerful than it originally was. Normally, the Shadow Assault charge is little more than a hop — albeit a very violent hop. This (admittedly very busy) GIF shows how it works as intended.
Focus on the guy with the yellow health bar above his head. That's Zeratul. See how he keeps leaping forward to attack the space marine dude in front of him? Now imagine if he could suddenly jump this far instead:
...or even further. What makes the exploit scary for many Heroes of the Storm fans is that it gives an already formidable character yet another powerful killing tool. Essentially, it transforms a relatively weak and unremarkable part of his kit into something that works the same way as "Hunt," a long-ranged charge move that fellow HOTS assassin Illidan can perform to leap in and surprise an enemy from halfway across the map:
Hunt is an extremely powerful move for targeting enemies foolish enough to isolate themselves late in a Heroes of the Storm game. But the reason it works on Illidan rather than Zeratul is because it's balanced out by other aspects of his character. He doesn't become invisible like Zeratul does thanks to his stealth ability, to name a major one. That's how stuff is meant to work in MOBAs — the seemingly ludicrously overpowered abilities are dialed back by the weaknesses the same character suffers from.
Blizzard clearly thought that Zeratul's newfound teleportation powers were unbalanced enough to pull the guy from professional-level play. As The Daily Dot noted today, this has left some HOTS teams like Team Liquid in an awkward position of suddenly being left without a long-standing character in the game they have come to rely on.
Just because Blizzard pulled Zeratul from tournaments doesn't mean he is necessarily overpowered with the newly discovered exploit, mind you. The popular eSports commentator Khaldor made a strong argument for keeping the assassin in the game as is last week, saying that the shadow assault exploit extremely difficult enough to pull off thanks to the precise timing and accuracy it takes to start the move aimed at one target, then almost instantaneously refocus on another target that's not in your immediate vicinity:
He therefore concludes that Shadow Assault should be seen as one of those wonderful little "oddities" in HOTS like the ones high-level StarCraft players used to discover — advanced techniques that separate the top players from the rest of the lot.
Zeratul is still active and happily slashing away at his enemies in normal Heroes of the Storm games, so really it's the HOTS community that will ultimately decide what to make of this nuance to his character.
(Personally, I still think that his other heroic ability is the better one to go with.)