Snapfire + Winter Wyvern

Why this works

Setting up Mortimer Kisses on a target locked by Winter's Curse seems like the obvious play, but it's a common mistake. The hero caught in Winter Wyvern's ultimate is immune to magic damage, meaning Snapfire's globs do nothing to them. The real, albeit less direct, synergy comes from using the ultimate on the *other* enemies. While they are forced to stand still and attack their cursed ally, Snapfire's ultimate can bombard them, applying damage and a heavy, stacking slow. It turns the lockdown into a wider area-of-effect problem for the enemy team.

In practice, this makes for a decent but conditional pairing. Their combined slows from other spells can be annoying in lane, but the game hinges on how well they can coordinate their ultimates in teamfights. A well-placed Curse from Winter Wyvern can force enemies to clump up perfectly for Snapfire to punish. However, it requires precise timing and for the enemy to group up in a specific way. If the setup isn't perfect, or if Snapfire is out of position, the whole concept falls apart, leaving them with a set of tools that don't always fit together neatly.