Not Triumph... "Ghost Eater"
I like when abilities and interactions are completely self-descriptive, in that reading the name is all you need to understand what it does. If I never played the game before and had to guess what the "Triumph" rune does I wouldn't have a clue, maybe gives you more ad when you get a kill? Hard to guess. But if I asked you what a "Ghost Eater" ability did you'd probably think you ate the ghost of something (probably a champion) and that it gave you some reward (probably health since that's what the act of eating usually does for lifeforms).
Thematically I think it's a better fit and I think this name would probably make it more appropriately categorized in the Domination tree which might have been where it belonged in the first place (debatable but I think there's a good argument to be had in favor of it).
And if a change like this did go through, the ability could get a cool new animation where the player's ghost travels to the slayer to be consumed, making it really obvious what's happening.
Thanks for the read :) [vlad-salute]