I'll open this discussion with this:
**Have you ever seen a Sona take half of your health at level 3?**
Because with **Thunderlord's Dance** mastery, Sona goes from poke to full out burst. A single Q-powerchord combo can shred the ADC to nothing, and then you can do it again in approximately 8 seconds, effectively killing them (assuming they don't/can't retaliate). This leaves this zoned to nothing, even without the help of the ADC. They cannot fight back against you, because a single rotation of your spells just gives you a powerchord once again, and that ADC will be gone.
My first experience versus the Thunderlord's Dance Sona was when I was playing yesterday, ironically as Sona. But not with the Thunderlord's Dance mastery (i had 18 points in the offense tree instead). But, I was facing a mirror support matchup: an enemy Sona, with Thunderlord's Dance.
My point in Deathfire Touch was no match for Sona's Q-powerchord combo. The slight burn on her was nothing versus her 1/2 health burst. Not even taking into account the ADCs, Sona was spamming Q while I had to spam W just to survive the burst. This caused us to lose lane and eventually lose the game. It was torture and I was baffled that I was being outpoked, despite going Ferocity while the enemy Sona had gone Cunning.
In what world is a utility focused mastery page supposed to out-damage an offense focused one? Sona is the master of bot lane poke, but this mastery might just make her viable--ACTUALLY viable, not "hoho breaking the meta!!" viable--for the mid lane.
Let me show you the last game I was in:
I was 1v2 the bot lane all game. I was able to out-poke AND out-burst Kog'Maw and Tahm Kench by just stacking up my Q-powerchord combo on them. They could not burst or poke me out because of my heal, and along with the **Meditation** mastery, my mana never ran dry. Knowing my ADC was gone for good, I eventually built AP instead of typical support items.
Why should Sona be able to burst a Tahm Kench? Isn't he the most anti-burst champion in the game?
Did you know Thunderlord's Dance scales off of 20% of your AP? Did you know that I took 2/3 of Kog'Maw's health with just a sheen, amplifying tome, spellthief's edge, and blasting rod? Making my AP a mere 73, and doing THAT much burst to an ADC?
Forget the OP ADCs. Sona will counter them all if this mastery is left uncheck on her.
But, I want this to be a discussion on the mastery, and/or Sona. Maybe she'll need a nerf in the end before Season 6 goes live.
Do you think this mastery, or Sona, needs a nerf? Has anyone had any experiences with the mastery that's overpowered on another champion? Have YOU faced a Thunderlord's Dance Sona? How did it seem to you?
_**EDIT: I mean "Thunderlord's Decree", not "Dance".**_