Underlord + Sven

Why this works

Thinking of Underlord as the perfect setup hero for Sven can be a bit of a trap. The idea is that Pit of Malice holds an enemy down for Sven to connect with his stun and God's Strength attacks. In practice, the root from Pit of Malice still allows enemies to cast spells or use items like a Ghost Scepter or Force Staff to survive the initial burst. The setup is not guaranteed. While Atrophy Aura makes it harder for enemies to fight back against Sven, their kits don't have a powerful, direct overlap. Underlord wants to control a wide area, while Sven often needs to jump and delete a single target instantly.

Their success together depends more on both heroes having a good game individually. Underlord creates space and weakens the enemy team with his presence and aura, which is broadly helpful for any carry. Sven uses that space to farm and find his own initiations with a Blink Dagger. A Fiend's Gate can bring Sven into a fight from an unexpected angle, but that's a powerful tool for any team composition. The pair can certainly function well in a teamfight, but they don't give each other a unique advantage that other heroes couldn't provide.