I generally like this item very much, and find it a priceless purchase in a lot of games. However, in my opinion it have so many strengths that it's unlikely to survive nerf hammer.
- It is the only source of magic resistance that have beneficial carry stats. Especially mana regen
- It worth pennies and is built from cheap and very useful components. Despite that, it is a part of one of the most powerful lategame artifacts.
- It basically halves the damage dealt to you. In terms of magical resistance, it even beats pipe and glimer active. But unlike them, it also heavily reduces other damage types, like OD, Silencer, Axe, Razor and Bristleback deal, and can be applies indefinitely.
Pretty much the only weakness it have, is it's inability to deal with BKB, and BKB was nerfed several times already.
Source: https://www.reddit.com/r/DotA2/comments/10o88g7/i_think_mage_slayer_is_busted_how_do_you_think_it/
