Abaddon + Ursa

Why this works

Running at a target as Ursa requires lockdown, which Abaddon doesn't really provide. While Curse of Avernus offers a slow, it's not the instant stun that lets Ursa build up his Fury Swipes stacks for a quick kill in lane. The defensive nature of Aphotic Shield is useful, but it's a reactive save rather than a tool for setting up aggression. Later in the game, some of their utility overlaps; Ursa can already dispel debuffs with Enrage, so the strong dispel from Abaddon's shield isn't always as critical as it would be for other carries.

This pairing often leads to a more passive game than Ursa wants. He thrives on early kills and objective control, but the lane can be too defensive to secure a strong lead. An Abaddon can certainly keep Ursa alive through the mid-game, turning gank attempts around with a well-timed shield or Borrowed Time. The problem is getting the snowball rolling in the first place. The duo has trouble forcing the issue and relies more on punishing enemy mistakes, which can make it difficult to build the momentum Ursa needs to take over the map before opposing cores come online.