Ancient Apparition + Juggernaut

Why this works

Securing kills with Omnislash becomes much more reliable when Ancient Apparition is on the team. The main synergy comes from Ice Blast, which prevents all healing and regeneration. This means an enemy caught by Juggernaut's ultimate can't be saved by a Mekansm, a support's heal, or their own lifesteal. If their health drops low enough under the effect, they shatter automatically, letting Juggernaut secure kills he might otherwise have to overcommit for. In the laning stage, a simple Cold Feet can also hold an opponent in place for a full-duration Blade Fury, which is often a guaranteed kill.

This combination primarily helps your team secure pick-offs, which you can then convert into towers or Roshan. However, the impact is very dependent on landing both ultimates. A missed Ice Blast or an Omnislash on a low-priority target means the combo is wasted, and both heroes have long cooldowns to wait through. Aware opponents will focus on positioning, spreading out to minimize Omnislash bounces and using items like Force Staff or Glimmer Cape to escape. Because Juggernaut can't lock targets down himself, this kiting is often enough to survive if the Ice Blast doesn't land first.