A few key professional players usually lead the wave of innovation in competitive play for any new or reworked champion.

With Kayn, who was released July 12, where he fits best or whether he even has a place in competitive still comes under debate. But those who have picked Kayn on-stage already have created a rich diversity of builds that suggest the Shadow Reaper may have multiple niches.

Kayn's transforming passive allows him to either take on a Rhaast form that deals bonus percent health damage, useful in a tank meta, or a Shadow Assassin form that looks to zip in and out of side lanes easily. Even among Rhaast users, however, build variations exist that suggest the debate regarding the optimal Kayn playstyle is far from settled.

"I think Kayn is really strong," Invictus Gaming jungler Gao "Ning" Zhenning told a League of Legends Pro League host after he first played the pick against LGD Gaming, "but many think he's weak, and he practically never shows up in Korean Challenger."

Part of what makes many hesitant to choose Kayn is the perception that he's an all-or-nothing snowball champion. Caster Aiden "Zirene" Moon recently highlighted Kayn's high base statistics and low per level base scaling in The Breakdown.

While the Rhaast form's percent of target maximum health damage modifiers somewhat mitigate Kayn's scaling weakness, getting the Rhaast transformation still requires an early snowball. In Kayn's first appearance in any major region, Team ROCCAT's Milo "Pridestalker" Wehnes had to delay his Rhaast transformation until 19 minutes.

Aside from failing to find early kills, Pridestalker paid a lot of attention to bottom and mid, dealing with mostly ranged champions, and whether the first transformation option is Rhaast or Shadow Assassin Kayn depends on whether more damage is dealt to melee or ranged champions. Shadow Assassin Kayn became his first transformation option, and he had to delay the choice, which set him even further behind.

Though the club of Kayn players in competitive remains somewhat exclusive, most agree that the Rhaast form has way more use in the current meta, especially in the jungle. Rhaast not only gives bonus percent target health damage modifiers to both Kayn's ultimate and Reaping Slash, but it provides a hard crowd control knock-up from Blade's Reach and sustain on his passive.

"Coming into mid game," Juan "Contractz" Arturo Garcia said in an interview after he played Kayn against Phoenix1, "you have your Darkin form. He's super good in teamfights. He has a knock-up on like a five second cooldown if you have 40 percent CDR, and his ulty is really good against tanks because it does max percent HP [damage]."

Most players dismiss the Shadow Assassin form. As the Rhaast form comes from dealing damage against melee champions, and ranged champions are much more common in the mid and bottom lane, a Kayn pick often telegraphs that a jungler will play around the top lane.

Junglers who pick Kayn often operate in the top half of the map because of the need to deal damage to melee attackers and get the Rhaast transformation. Provided by Riot Games/Twitch

Both Contractz and Invictus Gaming's Ning took this approach. They used Kayn to invade the top side of the map, peppering it with wards and counter-jungling their opponent before snowballing their top laner. Ning only played the pick against OMG and LGD in conjunction with Rumble in the top lane, while Contractz paired his Kayn with Maokai's easy crowd control to abuse Phoenix1's over-extending Cho'Gath.

The subtleties, however, come in how Contractz and Ning chose to build their Kayns. Contractz went into the Ferocity mastery tree to take less situational damage bonuses and Fervor of Battle to stack up with auto attacks in teamfights.

Ning, meanwhile, went for the Cunning tree. Greenfather's Gift gave him bonus damage on auto attacks when ganking from brush in river. He took standard minion damage and Runic Affinity masteries, but also situational bonus damage to low-health targets, Lethality and magic penetration instead of the percentage armor penetration from Ferocity, and most importantly, Thunderlord's Decree. The Thunderlord's Keystone gives Kayn even more all-in for the early game, dealing burst for the third attack against the same target.

One of Ning's games took Kayn's early power to the extreme with an Inhibitor turret dive at 11 minutes. Of course, it was painfully pre-emptive, costing top laner Kang "TheShy" Donggeun his life and luring Song "Rookie" Euijin into the mess.

Provided by Riot Games/Twitch

The Cunning tree suits Kayn very well for assassinations and early skirmishes, while Contractz's build emphasizes Kayn's teamfighting strengths a little more.

Despite the community's more willing acceptance of jungle Rhaast Kayn, however, European high elo solo queue players have been experimenting with the less favored Shadow Assassin form. Fnatic's Rasmus "Caps" Winther debuted mid lane Shadow Assassin Kayn against Misfits.

Caps' approach makes early game success even more important. "The most important thing when you start playing Kayn mid is you just don't die," he told Trevor "Quickshot" Henry in the post-game interview. "You get W's on enemy, and then you just don't want to trade."

Kayn mid lane has to get ahead to work well as a split-pusher in a 1-3-1 composition. He worked well as a pick for Fnatic against Misfits because Misfits struggles with sidewave control, making it vulnerable even in a meta where many teams ignore side lanes for teamfights in the middle of the map.

The Shadow Assassin form gives Kayn bonus magic damage for attacks and additional percent AD damage on Blade's Reach, but most importantly, it boosts the utility of Shadow Step. Shadow Step ghosts Kayn and allows him to ignore terrain. Not only does this ability give jungle Kayn interesting and unique gank paths, but with Shadow Assassin's unique ability to drop slowing effects and increase movements speed by a massive 70 percent within terrain, split-pushing Kayn becomes impossible to pin down.

"Not sure if Kayn mid is really good," Fnatic coach Dylan Falco admitted. "I think Caps played like 40 Kayn games in solo queue, and he was just like obsessed with the pick. As a coach, it was kind of difficult, because obviously it's a risky pick if you're playing something like a full AD assassin in a teamfight meta."

The Kayn pick came specifically against Misfits' Syndra mid. Kayn's ultimate allows him to negate Syndra's ultimate damage by infesting her, and taking the Death Fire Touch Keystone for multiple damage ticks and faster orb stacking allowed him to get a fast transformation and transition into a side lane role.

Misfits' compositions lacked anyone who could duel Kayn in a side lane efficiently, and when they sent Steven "Hans sama" Liv's Ashe to meet him, she dropped easily to Kayn's assassin potential against squishy targets. If Misfits tried to send multiple players to stop him, he drew on Shadow Step's utility to get away quickly, hide in walls, and return to split-pushing after the enemy left.

Kayn's mobility in his Shadow Assassin form makes it tough for opponents to wrangle him in the side lanes. Provided by Riot Games

Yet, if Fnatic balanced pressure improperly, Martin "Rekkles" Larsson's mid lane holding Varus became vulnerable to forces from Misfits' teamfighting composition. Luckily for Fnatic, Caps got far enough ahead to make it worth the risk.

Leading up to and since Caps' EU LCS Kayn mid Shadow Assassin debut, other EU mids have spammed him on solo queue. In the words of Chres "Sencux" Laursen, "I played a couple of solo queue games. Some of them were a bit int: a bit-run-it down, dying a lot. But, I mean, some games were good as well."

Luka "PerkZ" Perković's ranked match history shows seven Kayn games played with a 43 percent win rate. He had a much more colorful opinion of the pick than Sencux.

"I saw Caps' Kayn. He played it in scrims," and Perkz explained that G2 won laning phase in the scrim, but due to a mistake at Nashor, Caps started getting kills. "I was getting so triggered, and I was like, 'OK, I'm going to play Kayn, too.'"

"I play Kayn five games," Perkz continued, recounting his solo queue adventures. "I buy Mobis and run around the map and get kills everywhere. I'm like 'Holy s***, this champ is so strong.' But then, I played it in scrim myself, and I was so useless. I don't know how Caps won with Kayn in LCS. It blows my mind. Like. It really blows my mind how bad the enemy team must have been to lose to Kayn."

Given the state of the game, Rhaast likely has more use cases, but with his telegraphed top side fixation, he can be just as one-dimensional as mid Shadow Assassin Kayn.

At the very least, the initial weeks of competitive Kayn play have demonstrated that many options remain to explore further. A few rumblings of top Kayn have even begun for those wanting to ensure a quick Rhaast transformation, but at his very core, roaming and pathing potential make mid and jungle Kayn extremely attractive for controlling the map.