Quad Sona nerfs... or are they actually buffs (especially moonstone)?
26.11 Quad Sona nerfs may seem like Sona is getting slapped across the face, but these changes might actually increase the winrate of the best Sona builds.
TL;DR: 4x nerfs to W bot Aery/Revitalize/Dreammaker/Helia/Diadem/Moonstone/Dawncore Sona. Nerfs (other than Aery) dodgeable to good Sona players and current best builds. Moonstone changes are actually a huge buff for many games?
Aery: Plain nerf, no replacement rune, actually hurts Sona a little more than some other enchanters because of how auras work, but small in magnitude. Early poke unaffected.
Verdict: Actual nerf
Dreammaker: Good for Sona in the long run since this will lower her winrate without impacting actual Sona players (Bloodsong goers) at all. 45% of current patch Sonas go dreammaker. Balance equivalent of firing bullets into the sky to keep rent low, if you would. Actually better in some scenarios lategame (switching out Bloodsong for Dreammaker at full build for lategame teamfights) since the damage resist/damage procs apply more consistently. Resist more likely to get full value, damage can now apply to things like poke mage abilities instead of only on-hit. Think ~120 damage on Kai'sa W/Nidalee spears, ~60 damage on Ziggs/Xerath/Viktor etc poke. Sleeper buff in some games?
Verdict: Nerf doesn't affect good Sonas for 98% of games, and is a possible buff when actual Sona players would switch to it.
Helia: Hurts Sona a little but with bloodsong you'll often overcap the item regardless, hurts other champs more like Milio who can proc continuously so it's an actual output nerf on them. Nerfs interaction with Diadem where the healing is determined by damage output and not cooldowns. Otherwise output is usually cooldown/max value gated and not damage conversion gated on Sona.
Verdict: Likely a nothingburger. Matters more on enchanters less likely to immediately slam into the healing cap with their ability rotations. Diadem nerf.
Moonstone: Moonstone now (probably) uses un-multiplied (tooltip) values to calculate initial bounce value. Actually a huge buff vs GW. The HSP nerf doesn't really exist until your 4th item, and sometimes never does.
*****GW interaction: 100 W heal turns into 60 with GW. Moonstone currently then bounces for 0.3*60= 18 HP. Then is cut by another 40% into 10.8 HP, assuming the bounce target also has GW. But after these changes, heal of 100 turns into 60 as usual but moonstone bounce still heals 100*0.3 = 30, if it then bounces onto a GW target 30*0.6 = 18. That's 66.7% more healing being bounced if you initially heal a GW target! (1/0.6 = 1.67). Don't forget, in a 2v2 this means that Helia and W moonstone bounces heal 66.7% more if your teammate has GW on them.
HSP interaction: 100 W heal turns into 120 with 20% HSP. Moonstone would then heal 120*0.3*1.2 = 43.2 more hp. Now heals 100*0.3*1.2 = 36 hp. Basically moonstone had your HSP squared as a multiplier, which was kinda hidden by the fact that the bounce isn't that big in the first place.
Verdict: Moonstone + HSP significantly impacted at higher HSP values. If the enemy has GW on your heal target, you'd need sqrt(1.67) = 29% HSP for this change to be a healing nerf. Helia > Seraphs > Moonstone is now an even stronger 3 item build, as it dodges the HSP nerf entirely and only collects GW buff. Revitalize is even worse now too.
Conclusion: These changes do not meaningfully impact the best current Sona build of Bloodsong Helia Seraphs. Consider choosing between Moonstone and Dawncore lategame instead of getting both to dodge the nerfs, Staff of Flowing Water is great and a loss of just a 1.1 multiplier on the moonstone bounce is SUPER fake. Consider also that Sona is picked as an enchanter counter and these changes affect other enchanters far more than they affect her. Take advantage of the fact that Sona does not want to build dreammaker, overcaps Helia, and many times chooses between moonstone and HSP instead of stacking them.