lovely day in duo

Kriega, I'm not trying to be difficult for you or anything, but I'm legitimately asking because I don't know. Why not replace The Crusher with Brawler's Beat Stick since:
1) You don't have Qin's Sais in this build
2) It avoids the problem with the ult mez
3) Brawler's Beat Stick has more power, so wouldn't it be nicer in an ability build?

Or are you just getting The Crusher for:
1) extra damage from heartbomb combined with Heartseeker
2) Extra attack speed since you hardly have any in this build?

So this is a sort of an ability-based build due to the presence of Jotunn's Wrath. That said, the build is honestly a bit of a mess.

If Cupid wants to go the ability route, he's best going with Transcendence. He can then consider Jotunn's Wrath later in the build, but probably shouldn't be 3rd item.

Atalanta's Bow isn't a good item in this situation either. It's not a strong item in most cases...only one where I do appreciate it is for Medusa due to Sidewinder.

In the non-crit build, it's lacking the main DPS item I'd consider for him, which is Qin's Sais, even if going partial ability.

And with a crit build, the only time I'd consider that would be with 3x crit including Poisoned Star, Deathbringer, and Wind Demon, in combination with getting Devourer's Gauntlet (the standard basic attack ADC direction). It also just doesn't have enough pen.

So...here are 3 builds I'd suggest for Cupid:

• Ability-based: Transcendence, Warrior Tabi OR Ninja Tabi, Soul Eater, The Executioner, Qin's Sais, Jotunn's Wrath OR Heartseeker (HS could be purchased earlier too, as early as right after Tabi)
  
  
• Non-Crit Basic attack: Transcendence, Ninja Tabi, The Executioner, Qin's Sais, Odysseus' Bow, Bloodforge (at level 20, this puts his AS at 2.43, almost right at the cap, which is great for teamfight and Qin's passive)
  
  
• Crit basic attack: Devourer's Gauntlet, Ninja Tabi, Poisoned Star, The Executioner, Deathbringer, Wind Demon

As such, just don't recommend these builds.