Sona's Hymn of Valor (Q) and Power Chord (P) harass out-trade Soraka's Starcall (Q) poke, and Astral Infusion (W) healing can't keep up with the sustained pressure, bleeding Soraka's health down.

Yuumi becomes untargetable while attached via You and Me! (W) but has almost no lane poke, so Sona freely chips the ADC with Hymn of Valor (Q) and dominates the harass war.

Sona is squishy with no escape, so once Sett closes in with Facebreaker (E) he instantly melts her with Haymaker (W) and The Show Stopper (R).

Rocket Grab (Q) pulls the mobility-less Sona straight in and chains into Power Fist (E) for a guaranteed kill, and Sona has no dash to dodge it.

After Bone Skewer (Q)'s pull, Phantom Undertow (E)'s stun leaves low-health Sona with little room to escape. Pyke can finish with Death From Below (R) and then widen the lead through roams.

Death Sentence (Q)'s hook and Flay (E)'s knockback lock down the mobility-less Sona, chaining her completely even before The Box (R).

Zenith Blade (E) is a linear skillshot, but on hit it roots Sona and brings Leona to her. Shield of Daybreak (Q) and Solar Flare (R) then chain stuns, leaving immobile Sona vulnerable before she can cycle healing.