I reeaaaaally think that Shyvana doesn't work very well with Guinsoo's. I would try something else. Have you considered Wriggle's Lantern early game?

Unfortunately, I do play a full AD Shyvana rather than AS or AP build.
Concerning As:
- Dragom form loading won't be fast enough to load twice in a teamfight
- Although it's not bad it is not awesome.

As of AP, the reasons have been roughly mentionned:
- Low AP ratios
- 2 skillshots

For runes, excellent choice.
Why am I going full AD? Because Shyvana is a dangerous anti-tank. Her Q is just too stromg once maxed out along with Burnout [W].
roughly, may I suggest you to try:
Infinity Edge, Last Whisper, BloodThirster, Yuumou's/Atma (bad spelling D:), Merc's , Sunfire Cape

It works really great, doing good damage and criticals. Less tanky, however.

I won't vote because I haven't tried the build in-game, so it would be unfair to judge it as now.

P.S. Never liked Trinity Force on her, too little numerous bonuses

trIAlexCS

Ok, I know Phreak built similarly in the champion spotlight, but, IMO, hybrid Shyvana just isn't a good idea. She would be, if Burnout wouldn't be an ability that stacks with AD, and not AP, even though it deals magic damage. We all know that Burnout is Shyvana's bread and butter, so if AP doesn't work on it, why get it? Flame Breath is a good spell because of the armor reduction it does, certainly not because of it's damage, stacking AP to increase it's damage is in no way worth it, especially because of the fact that it has a very low AP ratio, and as a hybrid you will never build enough AP to make it work, like a mage does. Not to mention that it's a skill-shot and it can miss, so it's far to unreliable to build damage on it. Dragon Descent has some pretty hefty magic damage, but it's an ultimate, it won't be your "run of the mill" attacking ability. It's real strengths are in it's awesome utility and the armor and magic resistance bonuses that it gives(which also double when it's active). Building AP just for it, not worth it one bit.
I tried hybrid Shyvana too, but I gave up on that idea for the reasons I specified above, as well as for one more: Hextech Gunblade and Trinity Force cost a but load of money, and they're just not worth it for someone that benefits so poorly from AP, Shyvana doesn't have an OP magic damage nuke the way Jax has(Leap Strike), for example, Twin Bite is her most powerful nuke and it deals physical damage, enough said. Buying 3 AD items instead of Hextech, Trinity Force and Guinsoo's is a much more inspired choice. Of course those items have to also give a slow, health, attack speed, as Shyvana can't live without it and life-steal, as every self-respecting high AS auto-attacker should have. These items are Black Cleaver, Bloodthistier and Frozen mallet. These 3 things together do the job a lot better than the hybrid items: more health, more AD, more life-steal, the same attack speed, no useless AP for which you pay tons of money(they're a lot cheaper too).

Some might say that Hextech Gunblade is a good item to have, not for the AP, but for the spell-vamp. False! Burnout ruins the deal again: it's an area of effect spell, therefore all spell-vamp is reduced to 1/3 of the bonus. This means 6.5% spell-vamp on Burnout, totally not worth it, the life-steal on Bloodthirstier topples that in a minute.

In the defense department, apart from Wit's End, an item I think was tailor made for Shyvana( :)) ), there is another item to buy, one that gives armor. IMO, it has to be the one and only choice for almost each and every game. That item is, beyond a doubt, Sunfire Cape: it doesn't give as much armor as the others I saw in your list, but it also gives health(a good couple with Frozen mallet) and it's aura is something that leaves me speechless for the way it couples with Shyvana's Burnout. It's as if you would have the option to take Burnout to level 6, simply awesome. So, not only does AD Shyvana have more damage and is cheaper, but it's also a lot tankier, reaching a health of 3500, simply put, amazing... Building any AP on Shyvana is wrong, that's the reason I'll down-vote your guide. Hope you won't be mad cause of this fact and you'll appreciate the constructive criticism.

P.S. Shyvana is a very good champion to have on-hit effects on, and no on-hit effect is better than that of Black Cleaver as it repeatedly does the same thing Flame Breath does, and with Shyvana's high attack speed it means your target will get shred by your basic attacks, even though you don't have close to 100% critical strike chance, the way most AD carries have(melee or ranged), everyone knows that true damage is better than double damage that gets reduced by the opponents armor, this is the reason why the on-hit effect of Trinity Force doesn't compare to this one. Not to mention that the slow from Frozen Mallet is a sure thing, not a gamble.

Very thorough and nicely done. Can't wait to try this champion again!

Upvote. Good luck with your rating.

Thanks much man! I'll be improving the guide here soon, so check back! I'll pm you when I do.

Now I am only level 15. but I am going to put my word in.

I am going to up vote you on the second guide, the tank hybrid, I have found in my experience as Shy, staying in combat, makes or brakes her. If you have the staying power she dominates. Most guides on her seem to focus on her attack than her staying power, wile it is nice having all that damage, it means nothing if you can't stay alive long enough to use it, no one fears her dragon ult if she is too squishy.

To Banshees
You mean enemy team

Why Hybrid is available? Your Guide results : -> but why?
It does Magical Dmg, but scales with AD in Normal, but AP Dragon Form WHY HYBRID? Are Shyvana a Dragon, no just Half. Not at one Part of your Guide is really described why you play her this way (Hybrid), just how. Nobody tells himself the Question, is AP really good at her? or is it just fail. Or play you Katarina AD just because her Death Lotus scales a little bit with AD? not really at all.
To Edit: I read this Guide before downvoting, my Conclusion ->Fail->Downvote So where is the Problem right there
To Edit 2: If you really read my Comments on other Guides you will see mostly the same Problem i mention(Hybrid or Magic Pen Runes). Sometimes another. But how you can suggest that i downvote EVERY guide, because i want to be the best Guide. I read EVERY Guide, which i vote. Maybe you just want to be the Best by downvoting other Guides or by accusing my to doing this.
Edit: Sorry for my bad Eng

so you looked at a guide labled hybrid just to downvote it for being hybrid without trying it or reading the points the guide makes as to why hybrid is viable? Alright man.

Edit: Oh wait! I see your point, it's because you have a Shyvana guide as well that doesn't even use all the mastery points available to you with different playstyle that must be right, because it's yours! I'm sorry that my guide passed yours for a second on the ratings, but next time, read and TRY the guide before downvoting.

Edit 2: Good job downvoting just about EVERY shyvana guide that had a few votes as well for various reasons before even reading it. "I like how I do this better than how you do that!" when it's not even a comparable factor.

Abililty Power works with your W(Dragon Form) and E.
If you have your R (Ulti) all the Time i recommend this Guide, but fact is, you can use your Ult(Dargon Form) not all the Time, so is AP just a waste. A little bit is ok, for finishing with E or the burning Ground by W.