orb-effect

orb-effect: a skill that is passively given by an item or from the heroes skill itself; usually doesnt stack each other except under certain condition.
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The two golden rules:
1: Orb effects will never stack.
2: You may only place one buff per attack.

And as an information sticker:

* You will only get the effect that is listed in the box. If you get both, it says both. If there's some strange mechanics to it, it's listed in the legend.
* Eye of Skadi will be a melee eye of skadi if the unit that picks it up is currently in melee form. It will be ranged if the unit that picks it up currently has a ranged attack. Switching forms may or may not affect the form of the Eye of Skadi, it depends on the ability that changes your range
* Ursa Warrior is as of 6.44 a melee unit. Doombringer is a melee unit. As of 6.28, Banehallow remains as a melee unit in his ultimate form. Strength Morphling is no longer in the game.

Now, to the charts:

Spoiler:

Maim: "Sange", "Sange and Yasha"
Lifesteal: "Mask of Death", "Mask of Madness", "Helm of the Dominator", "Satanic"
Feedback: "Diffusal Blade", "Manta Style"
Chain Lightning: "Maelstrom", "Mjollnir"
Corruption: "Stygian Desolator"
Cold Attack: Melee: "Eye of Skadi melee"
Cold Attack: Ranged: "Eye of Skadi ranged"

Spoiler:

A quick explanation on how to read an excel chart:

Spoiler:

As seen in the ranged part, an Eye of Skadi and a Stygian Desolator would give you the Corruption orb effect, regardless of any other circumstances. However, on melee heroes, it says "Place". Looking in the legend, it tells you that "Place" means that the item in the highest priority slot will take effect, as well as the inventory priority order. I realize that my previous explanation may have been a bit ambiguous, so heres an image of the priority order: