A frame showing a carry with both Battle Fury and another axe in his inventory was discussed in the Dota community the other day. Yatoro on Anti-Mage lost his lane against Nature's Prophet and, after finishing Battle Fury, bought a Quelling Blade as well. The idea is simple: to clear camps faster and chop down the trees that Furion grows in his path.
A caveat right away. This is an observation from one specific match, not a proven meta discovery. But the mechanic itself is worth breaking down, because a whole layer of farming decisions rests on it.
Why the two items don't interfere with each other
Quelling Blade and Battle Fury both give a bonus to damage against creeps, but they are different items with separate effects. Each has its own cooldown for use and its own bonus. They don't "overwrite" each other the way auras do when they don't stack together. This is exactly what people argued about in the comments: some players were sure that a second axe was useless. Practice shows the opposite: when you swing at a creep, both bonuses trigger, and total damage against neutrals and lane creeps is noticeably higher.
It's important to distinguish two types of effects in Dota 2 here. Some bonuses stack by default (for example, an ordinary attack damage increase). Others are considered "unique": if a hero has two items with the same unique property, only one works. The reason the axes coexist is that they have different cooldowns and independent trigger conditions. Things like this should be checked in the item description and in practice, not by gut feeling.
Why this on Anti-Mage
Anti-Mage is a hero whose whole game is built on farming speed and the timing of the transition to a strong core of items. Every second he spends clearing a camp is a second when he isn't hitting the lane, heading into the jungle, or moving to the next forest. If he lost the lane, as in that match, he needs to make up for the lost experience and gold. Extra damage against creeps speeds up the "walk up, kill, move on" cycle.
An additional plus in this particular hero matchup: Nature's Prophet grows trees. Quelling Blade lets you chop them down faster than usual, which saves time on moving around the map. It's a narrow situation, but an instructive one: the purchase here answers a specific problem of the match, rather than simply being "bought because that's what's done."
When it's a mistake
An extra item costs gold and inventory space — there are only six slots in total. If you aren't losing your lane and aren't stuck on slow farming, a second axe is most often worse than something else: an item for survivability, mobility, or damage against heroes. A pro player can afford fine-tuned optimization because he knows the timing of his match down to the second. In a public game, the same purchase often turns into wasting a slot for the illusion of efficiency.
There's also a practical side. In the discussions under this episode there was a warning: don't repeat this in a public game, because you'll get reported. That's about the psychology of the match, not the mechanics. An unusual build that hasn't been explained to teammates is perceived as "feeding," even if the math is on your side. If you do decide on an unusual item, write a short note in chat about why you need it.
How to check it on your own example
Open a recording of any of your own games on a carry and find the moment where you bought extra items for farming. Ask yourself three questions: were you losing your lane at that point, how long did the camp-clearing cycle take before and after the purchase, and was there an alternative item that would have given more. If the answer to the third question is "yes," the purchase was most likely unnecessary.
This habit — checking an item against a specific problem rather than a general rule — is what separates a deliberate build from a memorized one. A hero with a good lane and a hero who lost it build differently, even if they play the same character in the same patch.
