Anti-Mage + Doom

Why this works

Casting Doom on a target often accomplishes the same goal Anti-Mage has, creating an inefficient overlap. Both heroes are designed to isolate and eliminate a single priority target. The problem is that Doom's ultimate silences and mutes the victim, preventing them from casting spells. This can directly reduce the damage of a follow-up Mana Void, which scales with how much mana the target has spent. You end up using two of the game's longest cooldowns to secure one kill, which is rarely a good trade when the rest of the enemy team can still fight back.

Beyond that specific interaction, the overall game plan is weak. Both Anti-Mage and Doom are exceptionally greedy heroes who need a lot of farm and space to come online. They don't create space for one another; they compete for it, forcing the team to play passively for a long time. This gives the enemy a massive window to group up, take towers, and control the map. Your team is forced to defend with limited resources while waiting for two cores to get their items. By the time they're ready to fight, the game is often too far gone to salvage.