Morphling + Zeus

Why this works

Trying to add some magic burst to a gank, Morphling can create a Replicate of Zeus and Morph into him. This gives Morphling access to Zeus's low-cooldown nukes, like Lightning Bolt. The main problem is that Morphling is an agility hero with a small mana pool. When he becomes a copy of Zeus, he can usually only afford one or two spells before running out of mana completely. This makes the burst potential much lower than it seems on paper, as he lacks the resources to spam spells the way a real Zeus can. It's a quick hit, not a sustained magical threat.

In practice, this combo is all about securing a specific kill. The replicated Zeus can add that little bit of extra damage from anywhere on the map to finish someone off, especially if the real Zeus follows up with Thundergod's Wrath. The downside is that it's a significant commitment for the Morphling. He has to stop what he's doing—whether it's farming or right-clicking a priority target—to use a mana-intensive, short-lived burst of magic. If that burst doesn't secure a crucial kill, Morphling has effectively wasted his time and mana for very little gain.