Tryndamere has natural Crit chance, so taking a bunch of Crit runes would seem like a good idea. I've done it, gotten a pentakill out of it.

thoughts?

Crit damage runes suck early game. Armor pen or AD runes not only give you similar damage crits, but stronger non crits.

Even on Tryndamere, running them means your early game is going to be awful, in exchange for a small boost late game. But when you're already critting hard, critting harder isn't going to make a whole world of difference. That pentakill you got? Doubtful that it was because of crit damage runes.

And by late game, I mean the part where you're farmed to the point where you crit reliably. Which would mean an IE and a dancer/shiv on Trynd, which is going to take you a while to get.

And on top of this limitation, crit damage runes are rediculously expensive in terms of IP cost. They're the biggest newbie trap in the game outside of tier 2 runes.

I do lke the idea of them on Pantheon though. Secure that kill at any level.

Lets try some math. The problem is basically that your crit chance is very low, which means that crit damage is not nearly as effective as it ought to be. It doesnt break even till like 50% crit or so. Even then, an IE effectively makes it worse when achieved.

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Assume you have 60 AD, 1.0 AS = 60 dps for simplicity.

Lets use 10 Quints to illustrate our points.

Lets assume you have MAXED FURY for 35% crit. Pretty generous huh? Especially since Trynd really wants to use it for healing and sustain.

His DPS is now 60 plus 35% chance of adding another 60 dmg all times 1.0 AS
== 60x1.35 = 81.

option 1: 10 AD quints: +22.5 AD = 82.AD x 1.35 x 1.0 = 111 DPS or +30 DPS.

option 2: 10 AS quints: 35% AS = 60x1.35 x (1.0+.35x.665) = 81 x 1.23 = 99.5 dps or +19ish dps.
(this is expected cuz I gave a lot more AS than youd normally get).

option 3: 10 Crit dmg quint: +44% crit dmg.
DPS = 60 + 35% chance of adding 60x1.44 xtra) times 1.0 AS
= 60 + .35x60x1.44 x 1.0
= 60+30 x 1.0
= 90 DPS ONLY +9 DPS!!!

You can clearly see that the crit dmg is by far the worst option. AS is normally gonna be better in comparison if you plugged in a realistic .7 instead of 1.0.
But the only way crit dmg is worthwhile is if you have crazy amounts of crit chance,. This just DOES NOT HAPPEN until way late game.

And by late game your runes are relatively unimportant compared to the mountain of stats you have from items and levels.