With every new patch, there is a public data file released that contains all the data concerning the cards in the game. This data doesn't always reflect exact functionality, but it does often contain changes that don't make it to patch notes. This patch had a few more interesting ones than usual, so here they are.
Flavour text changes
The following cards have apparently had their flavour text changed. These sound more like the reward track bios for these champions than flavour texts, so I'm not sure what they're doing on cards. These strange changes in the community data may not reflect actual changes within the game, but I don't know why else they would be edited. It's particularly odd that Whimsy was changed but not Lulu's Whimsy. EDIT: As u/EmpressTeemo pointed out in the comments, the three champs that seemed changed are also the ones featured in the new Lab, so these shouldn't reflect any card changes. Hopefully!
Trundle (lvl 2)
The Avarosans refused. Trundle gestured, and, like an avalanche, the trolls descended with such momentum that it carried them on for miles afterward, deep into the Avarosan tribelands, battering and breaking everything in their path without reserve.=>Trundle is the savage king of trolls who dominates the Freljord with his fierce and hardy troll army.
Whimsy!
"Adoribus!" - Lulu=>The yordle mage Lulu supports her pals and squirrelifies her foes with her own unique brand of magic.
Aurelion Sol (lvl 1)
"I don't care what you write about me, you middling creature! Just make sure I'm described as handsome. And magnificent. And also very, very intelligent. Can you spell that?"=>Aurelion Sol is an ancient cosmic dragon who has forged countless stars and planets. From Targon's peak he plots the destruction of the... "middling" world of Runeterra.
Dev cards
Several new uncollectible cards were added to the public data files. These new cards have recycled artwork, nonsensical wording, and "dev_[cardname]" instead of a cardcode. I suspect these were testing cards for the upcoming Lab, or possibly even the Lab cards themselves, though that seems unlikely to me since Lab cards have never appeared in the public data before.
Miscellaneous
Unspeakable Horror and Ravhun now specify that they make non-champion cards. Also Revitalizing Roar is clearer and Monkey Business and Jack, the Winner are shorter. That's nice.
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