Shadow Shaman + Slark

Why this works

Trying to lock down a single target for Slark is where this pair finds its footing. Shadow Shaman’s disables, especially the long duration of Shackles, give Slark the perfect window to land Pounce and build up his Essence Shift stacks. A well-timed Hex into Shackles can hold an enemy in place for a long time, letting Slark gain a significant agility advantage early in a fight. Slark doesn't need much help sticking to a target, but getting that initial lockdown from a teammate like Shadow Shaman makes his job much easier.

This dynamic is most effective during the mid-game, where the two can roam for pickoffs on isolated heroes and then convert those kills into towers with Mass Serpent Ward. The strategy is very focused on a single target, though. Enemy teams with good saves, Force Staffs, or a tendency to stick together can disrupt the combo by breaking Shackles or saving the focused hero. The success of this duo often depends on their ability to find those ganks before the enemy team is prepared to counter the obvious lockdown.