User blog comment:Leyrann/Why Chalice of Harmony is OP/@comment-4881935-20120827164833/@comment-4834593-20120828060531

Mana brings disadvancements in that you need to manage your resources. Because Energy, Fury, Health or just no secondary bar don't have this, they need to get another disadvancement. Energy has that you can't faceroll, because you have very little, but you have a way to get some back, and you have just very fast regeneration. The others, those without costs on their abilities, will have longer cooldowns or lower damage to balance it out. This means that they have, in fact, a lower damage output than you have, however, if you both poke and sustain (from items or abilities) long enough, they in the end outdamage you because you have no mana to use your abilities. At this point, Chalice works wonders, because this point either does not exist, or is delayed a long time, longer than with, say Philo Stone. As long as you did not reach this point, you got the advancement in lane.

A very good example for this was my Riven vs Yorick lane. I had to tower hug, last hit as much as I can, and all the time shield-dash to the ranged minions to hit them, after which I tried to last-hit another with my W if possible. However, as soon as he was out of mana, I rushed towards him, did what Riven is good at (dealing her highest damage potential, despite the enemy running away), and killed him. Because I knew he could not retaliate. His Tear of the Goddess delayed this point for a long time. Would he have bought a Chalice with it, I would have had to tower hug until the laning phase was over, or until my jungler would gank (and I must say, I don't like ganks. Not even from my own team. My farm was still about equal to Yorick's farm, so it was okay for me).