Riot just released two new blood moon skins on the pbe. http://www.surrenderat20.net/2014/11/1119-pbe-update.html Riot are you just going with the rule of cool now with the blood moon line? is the blood moon skin line no longer canon ? it doesn't seem like elise would fit into either of the roles of the blood moon play.
MrBuffington1 votesI was pretty frustrated when I saw too, but I went back and checked my facts. ShadowKnight1224 says it well; apparently "Blood Moon" isn't just for that lore event, but actually just anything that is frightening in Ionian culture. Combined with Ant in Oz' comment earlier, it makes sense that Ionian culture would have scary stories about Thresh and Elise as well.
Valaran Nara3 votesEspecially when
Elise's human form "is a mask". Let's not forget that there are such things as "Jurogumos". Last I checked, they are a type of Yokai that spawns from a spider gaining a human form. They will tempt you. They will bed you. Then they will DEVOUR you.
Which also reminds me. 
Thresh is now considered a Shinigami (death god). He'll reap all of their souls. @n@ ALL OF THEM! 
Shíny1 votesYeah seems to make sense, i hope riot makes new stories to go along with the new blood moon skins :) Ionia probably has many traditions celebrated at the festival of fire. I wonder if elise in ionia's eyes is like how valaran nara described elsewhere here.
MrBuffington1 votesYea, Kalista and the Harrowing has gotten me pretty curious about the Shadows Isles lore that hopefully will accompany all of it, it'd be pretty cool to see more connections between Ionia and Shadow Isles
Diahane1 votesI was pretty frustrated when I saw too, but I went back and checked my facts. ShadowKnight1224 says it well; apparently "Blood Moon" isn't just for that lore event, but actually just anything that is frightening in Ionian culture. Combined with Ant in Oz' comment earlier, it makes sense that Ionian culture would have scary stories about Thresh and Elise as well.
Ant in Oz's comment made sense for Kalista because they crafted a lore for her which makes her a global scope kind of metropolitan legend, but I can't see why Thresh and Elise should be renown in Ionia so as to be represented in their festival. Blood Moon being for things other than the festival looks to me like a recent addition to justify their choice, but I will gladly stand corrected if you have references of things being this way from the start.
MrBuffington1 votesAccording to Valaran Nara, Thresh and Elise have analogues in Japanese mythology, which is sort of close to Ionia in some ways (I mean, Yasuo is Ionian, he's basically a samurai). I don't think Bloodmoon is restricted to the festival that Shen and Akali put on, more "Bloodmoon" is a description of a certain appearance, typically given to things that are spooky in Ionian culture. Shen has a Blood moon skin because he was playing the part of an evil spirit, Akali has one because she was playing a character who sort of embraces or overcomes that evil spirit by putting on a Bloodmoon mask herself.
From what I understand, Bloodmoon is a larger aspect of Ionian culture, where the festival was just one event that was put on, where Shen and Akali dressed in Bloodmoon style clothes to represent the play they were in. It's kind of like the grim reaper being a symbol for death, and some people putting on a show where one of them dresses as a grim reaper to symbolize someone dying or something.
Diahane1 votesAccording to Valaran Nara, Thresh and Elise have analogues in Japanese mythology, which is sort of close to Ionia in some ways (I mean, Yasuo is Ionian, he's basically a samurai). I don't think Bloodmoon is restricted to the festival that Shen and Akali put on, more "Bloodmoon" is a description of a certain appearance, typically given to things that are spooky in Ionian culture. Shen has a Blood moon skin because he was playing the part of an evil spirit, Akali has one because she was playing a character who sort of embraces or overcomes that evil spirit by putting on a Bloodmoon mask herself.
From what I understand, Bloodmoon is a larger aspect of Ionian culture, where the festival was just one event that was put on, where Shen and Akali dressed in Bloodmoon style clothes to represent the play they were in. It's kind of like the grim reaper being a symbol for death, and some people putting on a show where one of them dresses as a grim reaper to symbolize someone dying or something.
But these are not canon facts. The only thing which was canon was the JoJ piece with Akali and Shen, in which they enacted the story of Reina fleeing from an evil spirit until the day she resolved to face it, thus making it disappear. But Reina nor her mask was supposed to be about spookiness. In the description of the festival in the JoJ there's no reference as well to this idea. What's there is:
During the night, Ionian citizens were treated to various musical and theatric performances pertaining to Ionian history or legend.
which could be used to argue the new Blood Moon skin refer to actors playing characters for this performances. But here lies the problem: why are Elise and Thresh Ionian legends? While Kalista is explainable due to her global scope metropolitan legend and Thresh is kind of explainable (not completely, because if he wanders everywhere his deeds in Ionia shouldn't be so many or so frequent to have him become a full fledged mythological creature) because his short lore now says he wanders Runeterra, it doesn't make sense for Elise to be a legend. That would rather hinder her job of deceiving people into following her so that she can offer them to Vilemaw...
MrBuffington1 votesI mean, I have nothing to do with the lore or Riot, so I can't say for sure, but it still makes sense to me. Both Thresh and Elise are ageless, so they could have been around for long enough to become legends (I mean, the game is called League of Legends, which can be taken to mean the cast of characters is a league of legendary people across runeterra, with or without the retcon). As for Elise, she's pretty deceptive in her means; in her lore, her followers don't seem to fully understand who she is until she's about to sacrifice them. It's precisely that she is a legend is how she is able to deceive them; a person might not believe in vampires or something, they're mythological but sort of dismissed as a fantasy, so her followers might think that of Elise and Vilemaw, so they think they're safer than they actually are.
Diahane1 votesI mean, I have nothing to do with the lore or Riot, so I can't say for sure, but it still makes sense to me. Both Thresh and Elise are ageless, so they could have been around for long enough to become legends (I mean, the game is called League of Legends, which can be taken to mean the cast of characters is a league of legendary people across runeterra, with or without the retcon). As for Elise, she's pretty deceptive in her means; in her lore, her followers don't seem to fully understand who she is until she's about to sacrifice them. It's precisely that she is a legend is how she is able to deceive them; a person might not believe in vampires or something, they're mythological but sort of dismissed as a fantasy, so her followers might think that of Elise and Vilemaw, so they think they're safer than they actually are.
Don't get me wrong, I'm not questioning anyone's ability into making sense of this, this explanation of yours could as well fit the matter and I thought something along those lines too. What I wanted to point out is that all this is an addition, an edit of their previous take on the subject. Summarizing, it's just the result of a retcon. There was no such reason as those you listed before to justify those skins. To justify them, the retcon is needed and the matter is just as I noted in another topic some time ago, this line of skin was touched by the retcon and so it's not surprising that these skins are now out. This said, the problem I do have with it it's that, like everything with the retcon, Riot's stance is unclear. Without full form stories or wider breath stories about Runeterra we don't basically know what the new lore is and are left with just hypothesis as to whether and why these skins could have a connection to actual lore. The absence of a Riot's official statement on the whole line of skins or of any sort of lore like the JoJ regarding this is but another example of the bad communication pattern regarding lore.