What Makes Skin So Rare?
Not every old League of Legends skin is actually rare. Some have been around for years but were still available to millions of players at some point. The really rare ones are a different story. They were often tied to a specific event, an old promotion, a collector’s edition, or a period of League that most players today never experienced.
The biggest factor is simple: you can’t get them anymore. Only a limited number of players once had the chance to unlock these skins and that opportunity is long gone, its rarity can increase over time. That’s why skins like PAX Twisted Fate, Black Alistar, or King Rammus are still talked about years later.
#1 - PAX Twisted Fate (The Rarest of Them All)

PAX Twisted Fate was handed out at PAX 2009. Players who attended the event could get a code for the skin. Riot later disabled the old codes, so you can't just find one and redeem it today. The skin is still sitting on the accounts of players who got it back in 2009, which is why it has become one of the biggest flexes in League.
#2 - Black Alistar (2009 Pre-Order Bonus)

Black Alistar was included with the Digital Collector's Edition of League of Legends when the game launched in 2009. If you bought that edition during the original release period, you got the skin. There was no separate way to buy it later. Fifteen years on, most players have never even had the option to get it.
#3 - King Rammus (A Closed Beta Reward)

King Rammus was a reward for players who took part in the League of Legends closed beta. That's it. You had to be playing before the game officially launched. There wasn't a shop rotation or event you could wait for. If the skin is on your account, you've been around since 2009.
#4 - Young Ryze (A Collector's Bonus)

Young Ryze goes all the way back to the original release of League. It was tied to the early retail Collector's Edition and pre-order period. Back then, buying a physical copy of League could get you things that simply don't exist anymore. Young Ryze was one of them. There is no current way for a new player to add it to their collection.
#5 - Silver Kayle (A 2009 Exclusive)

Silver Kayle was another bonus from the original Collector's Edition in 2009. You needed the physical edition of the game to get the skin. That was over 15 years ago, and the original distribution is long gone. Silver Kayle itself isn't particularly crazy-looking compared with modern Kayle skins, but that's not really the point. It's one of those skins that survived from the first year of League.
#6 - PAX Jax (A PAX Event Code)

PAX Jax was given away at PAX Event during the early years of League. Players received a code at the event and could redeem it on their account. Those original codes are no longer usable, so the only people who still have PAX Jax are the ones who got it back then. It's also one of the few skins that instantly tells other players you're using something from League's very early days.
#7 - PAX Sivir (A PAX Event Code)

PAX Sivir came from PAX 2011 and was the third original PAX skin. Just like PAX Jax and PAX Twisted Fate, it was distributed through event codes rather than the normal League store. Riot later released Neo PAX Sivir, but that's a separate skin. The original PAX Sivir is the rare one collectors are after.
#8 - Rusty Blitzcrank (A Short-Lived Skin)

Rusty Blitzcrank is probably the strangest skin on this list. It was actually sold in the store, but only for a short time. Riot eventually pulled it because of its low-quality model and never brought it back. So unlike the PAX skins, there was a period when anyone could buy Rusty Blitzcrank, you just had to be playing League at the right time.
#9 - Riot Squad Singed (Limited Riot Promo Event)

Riot Squad Singed is another relic from early League. The skin was connected to Riot's promotional events and was also available in the store for a limited period.
#10 - Ufo Corki (Reward for Early Players)

UFO Corki was given to players who created their League account before January 14, 2010. There was no special purchase involved. You just had to be there early enough. At the time, nobody could have known that League would still be one of the biggest games in the world more than a decade later. Today, UFO Corki is basically a badge from the first year of the game.