Kayle has no mobility or escape until level-6 Divine Judgment (R), so Viego latches on with a charged Spectral Maw (W) stun and grinds her down in the early lane with Sovereign's Domination (P) lifesteal auto-attack chip damage.

Kassadin has no melee sustain before level-6 Riftwalk (R), so his health keeps getting shaved by Viego's Sovereign's Domination (P) lifesteal chip damage, and he gets deleted by a full-charge Spectral Maw (W) stun all-in.

Yasuo's Wind Wall (W) can't block Viego's melee Blade of the Ruined King (Q) or Spectral Maw (W), so his only defensive tool is neutralized, and he cedes the trade to Viego's empowered Blade of the Ruined King (Q) combo chip damage.

Vladimir's early trading is weak due to Transfusion (Q) heal reliance and Tides of Blood (E) health cost, so before he scales he hands over first blood to Viego's full-charge Spectral Maw (W) stun all-in.

Nasus uses Wither (W) to shut down Viego's Sovereign's Domination (P) lifesteal autos and Blade of the Ruined King (Q) trades, tanks through the return damage, and stacks Siphoning Strike (Q) safely.

Renekton interrupts Viego's Spectral Maw (W) combo with the empowered-auto stun from Ruthless Predator (W), and dominates early trades with fury-based damage and the Slice and Dice (E) double dash.

Darius cancels Viego's dash engage with the Apprehend (E) pull, and after stacking Hemorrhage (P) to five he punishes the all-in with a true-damage Noxian Guillotine (R) execute.

Fiora parries and counter-stuns Viego's Spectral Maw (W) with Riposte (W), and holds the sustain edge in extended duels through Duelist's Dance (P) vital chip damage.

Shield Vault (W)'s targeted stun and Comet Spear (Q) poke let Pantheon control melee trades from levels 1–5. Viego is vulnerable to being stunned first while charging Spectral Maw (W), giving up the health advantage.