Drow Ranger + Keeper of the Light

Why this works

Picking Keeper of the Light to support a Drow Ranger doesn't create a clear power combo. The main benefit is in the laning stage, where Chakra Magic allows Drow to use Frost Arrows more often for harass and kill attempts. Outside of that, their kits don't have much specific overlap. Keeper of the Light wants to channel Illuminate from a safe distance, while Drow wants to be close enough to attack and is often kiting on the edge of fights. Blinding Light can even be disruptive, pushing enemies out of Drow's attack range when she's trying to finish them off.

As the game develops, these heroes tend to operate independently. Drow Ranger focuses on her own positioning to maximize Marksmanship damage and land her silence. Keeper of the Light manages waves, provides vision, and looks for big teamfight spells. While they don't get in each other's way, they also don't actively enable each other beyond the early mana sustain. Success comes down to how well each hero can execute their own game plan, rather than from any special teamwork they unlock together.