League of Legends' cursed troll Trundle is getting a makeover, considering his brutish visage this may be a move by Riot to position him as the next face of L'Oréal or it could be just to update him with the times, keep him street, for the kids. If you were worried his trip to Trinny and Susannah might leave Trundle packing less punch when it came to brawling the centre lane then you needn't worry, answering a few questions from forum poster OH NO ITS LU BU, Riot's GrumpyMonkey has explained that the changes are largely cosmetic, though he does hint that his lore too may be altered.
LU BU asked whether Trundle would be keeping his immense club or whether it would be downsized for something a little less outsized; if he will be the same old likeable deformed troll that he was before; whether his abilities are being tweaked along with his look; and, lastly, if his new look would invalidate any old skins players had purchased and would they be able to get a refund if they were.
GrumpyMonkey responded saying that the club is there to stay but his lore was "something we are still working on, the lore team has lots of ideas for him that are still in progress". Suggesting that it will be tweaked and respun by writing team. Monkey didn't go into detail about what they were looking at changing.
Monkey wouldn't say if the stats of Trundles moves were being changed at all, though he would admit that their look was getting a seeing to. New particle effects and animations, possibly.
The most important question, about whether owners of Trundle skins can expect to use them again, well, Monkey wasn't entirely open on the subject, saying "This is a bit more complex. His skins have been refitted to the new look. How we implement the changes is still to be determined. I will say it's safe to expect messaging on this particular subject later." So, that could be either a replacement skin, refund, or nothing at all.
I've contacted Riot to see if we can get any clearer answers.