What about Manamune/Muramana?

This item is currently being considered by less and less champions. After rework I can only see having it as a core item. Even doesn't build it anymore due to his mana cost buffs and buffs to lethality. doesn't build it either since the nerfs to his Q and most people go crit with him now.

The problem with this item is that it stacks too slowy and most offensive AD champions either need to stack lethality and snowball early, or to build crit and scale into late game. Neither options give you the freedom to build Tear because it really gimps your early game, yet it doesn't give as much power as a crit build late game. In addition, it requires you to have low cooldown abilities so that you can stack it reliably and fast enough (the ironic thing is that there are some AD champions that fit into this category but they are manaless so they are obviously not going Tear). Lastly it requires you to have mana issues to begin with, since you will not build this item if you don't need to worry about mana.

You also preferably need a single targeted ability. Although this item procs with autos, it is best used when you can combine it with single target abilities to proc it more times in a single combo.

And that's the problem. No champion in the game fits into the aforementioned category. Even champions that could theorically work well with Muramana (in addition to the aforementioned Varus and Jayce, there is also due to them having spammy abilities, single target abilities, and/or ways to double proc Muramana's damage) have better build paths and thus go with them. The potential late game damage from Muramana isn't worth the loss of early game power from building a Tear.

Ezreal is the only exception because he can't really go lethality due to all of his abilities except his Q being magic damage. Also he can't go crit either since this same Q cannot critically strike. He doesn't have a better build path, so Tear is the way to go with him.

What can be done to make Manamune and Muramana a more attractive option for champions to go? Does this item need to be reworked? Does it need to stack faster?