Tip
Karthus will create a leveling gap, so try to fight him often right after you purchase items after your first recall. Focus on dodging Karthus’s Lay Waste(Q) when fighting him.
Shyvana vs Karthus

Karthus will create a leveling gap, so try to fight him often right after you purchase items after your first recall. Focus on dodging Karthus’s Lay Waste(Q) when fighting him.