Death Prophet + Shadow Fiend

Why this works

Sharing farm on the map becomes a real problem. Both Death Prophet and Shadow Fiend are greedy heroes who want to accelerate their farm using spells like Crypt Swarm and Shadowraze. They naturally want to occupy the same central parts of the map, clearing waves and then rotating into the nearby jungle. This creates a fight for resources within your own team, slowing down key item timings for both cores. They also each bring a ton of damage but lack the reliable stuns to set the other one up, making them less than the sum of their parts without help.

This tension between them creates a tempo clash in the mid-game. Death Prophet will want to group the team and push down a tower every time Exorcism is ready. Shadow Fiend, on the other hand, usually needs to farm for longer to hit an important item like a Black King Bar before he feels comfortable fighting. The team is left with two competing game plans: one hero wants to force objectives, the other wants to farm. This often leads to hesitant pushes or taking fights where one core isn't ready.