Today I’ve got another rune discussion for you, branching off the magic penetration guide I made the other day. If you’re a physical DPS player – Ashe, Warwick, Twitch – you’re going to be going after critical strike items, typically culminating with Infinity Edge. Few things are quite as fun as burning down a Fiddlesticks with a few quick crits. So how should you spend your IP: critical strike chance runes or critical damage?

There are two sides of the debate. For critical damage, the idea is that you are increasing your damage by means only available on two items in the game: Sword of the Occult and Infinity Edge. Those are the only method by which you can increase your critical damage and one, the Sword of the Occult, can be fairly unreliable. If you’re a Shaco player, crit damage can be invaluable as it increases the damage caused by Deceive. Early game you can nearly one-shot players if you have a full crit damage page.

But crit damage runes are expensive. Very expensive. The crit chance folks would argue that crit chance has wider application and can more effective swing the early game in your favor. Bumping your crit chance by as much as 20% means you should win almost every stand and fight situation at level 1, and your harassment gets a big boost too. It’s easy to scare someone off with a few early 120+ hits. As abundant as critical chance items are, you could easily make the argument that runes allow you to forego some of those items in favor of damage, which could in turn lead to more Bloodthirster stacks, which gets very scary for the other team.

For my IP points, I’d go for crit chance. They’re cheap, provide a solid benefit, and can help push you toward a few more wins until you’ve got the IP to upgrade to crit damage.