Bounty Hunter + Phantom Assassin

Why this works

Applying Track to a target gives Phantom Assassin the vision she needs to commit with Phantom Strike from a long distance. The bonus gold from a successful kill also helps accelerate her farm, potentially letting her hit key item timings sooner than she otherwise would. Bounty Hunter’s scouting reveals isolated heroes, setting up the exact kind of single-target pickoffs that Phantom Assassin excels at. This gold advantage isn't limited to PA, as the whole team benefits, helping to create a wider economic lead from a few successful ganks.

The strategy relies heavily on that early and mid-game aggression. If you can’t find those pickoffs, the pairing offers very little. Bounty Hunter doesn’t provide any stuns or saves to help Phantom Assassin survive in a full-blown teamfight, and neither hero is great at dealing with a coordinated five-man push. The duo's effectiveness drops off if the enemy team simply groups up and forces objectives. This makes the game plan very specific, and if the enemy identifies and counters it, the synergy mostly evaporates.