Bane + Zeus

Why this works

Securing a kill on one hero is straightforward with this pair. Bane can use Fiend's Grip to hold an enemy in place, which gives Zeus a completely free window to land all of his magical burst. It’s an effective way to remove one person from the fight before it even starts. The catch is that this isn't a special interaction. Bane provides this same setup for any damage dealer, and Zeus can capitalize on almost any form of disable. They don't unlock anything new in each other; they execute a basic gank that many hero pairings can accomplish.

Across the rest of the game, their objectives don't overlap much. Bane is focused on disabling a single, high-priority threat, often putting himself in danger to channel his ultimate. Zeus is concerned with positioning far in the back to hit the entire enemy team with repeated, widespread damage, and using Thundergod's Wrath to clean up kills or assist globally. They operate in different spaces and focus on different targets. While they don't get in each other's way, they also don't amplify one another's core game plan, leading to a very neutral, predictable outcome.