Puck + Spectre

Why this works

Getting caught out of position is suddenly much more dangerous. Puck can lock a target down from range with Dream Coil, and Spectre can immediately join the fight with Haunt from anywhere on the map. This combination makes it almost impossible for a lone hero to escape. Puck provides the magic burst and control with Waning Rift and the Coil's stun, creating a perfect window for Spectre to arrive, isolate her target with Desolate, and finish them off. The two heroes cover each other's weaknesses perfectly for picking off stray enemies.

This pairing comes online once Spectre gets her ultimate and Puck has a few core items. Their goal is to control the mid-game by punishing anyone farming alone, creating space and converting kills into objectives. The main problem is getting there. Both heroes can have a difficult laning phase and are vulnerable to early aggression. The enemy team's best bet is to apply constant pressure to keep Spectre's farm down and delay Puck's timings. If the duo can survive the early game, their map-wide ganking potential becomes a serious problem.