Clinkz + Nyx Assassin

Why this works

Putting two invisible hunters on the same team looks scary, but their goals are often too similar. Clinkz wants to find an isolated hero and unload Burning Barrage, usually killing them without much help. Nyx Assassin also excels at solo pick-offs using his own burst and stuns from stealth. They don't combine into something greater than the sum of their parts; they perform the same job in parallel. While a Nyx stun can set up a kill, Clinkz is often self-sufficient. Applying both heroes' full damage to one support is frequently overkill.

This overlap gives opponents a very clear counter: buy lots of detection. A map with Sentry Wards everywhere makes life difficult for both heroes at once. For this pair to succeed, Clinkz and Nyx have to coordinate their movements carefully. They either need to split the map to stretch enemy vision thin, or time their ganks so they aren't both blowing major spells on the same target. Lacking that coordination, they often end up competing for opportunities while the enemy team groups up and pushes with their vision advantage.