Welcome to my first Mobafire guide! This is a S5 Zac tank jungle guide. Zac is among the tankiest champs in the game rivaling Sejuani, Cho'Gath, Nautilus and other tanky tanks. He is my favorite of the tanks because he is extremely fun to play and extremely hard to kill. One of the main reasons I like Zac is because not only being very tanky he also has good CC and pretty high amounts of damage if built right.

Pros:

SO TANKY
Extremely good sustain
Good damage
Good escapes
Good ganks
Good CC
No Mana/Energy
Strong Mid-Late game
Awesome area slow with Q

Cons:

No high burst damage
Mediocre Cooldowns
Good Rune set is expensive
E is skill shot dependent
Squishy early game
Hard to play
Slow clears early on if not done right

Quintessances:
Health Regeneration x2:
These are pretty much required as you need the regen for early game to not die. You could get away with just having the seals and glyphs but its way better to have both quints.
Ability Power x1:
This is just so you have that extra bit of AP for helping with clears and ganking early on, this wont do you much for late game as it doesn't add anything to your W as 5 ability power does not scale nearly that good on it(that would be ridiculously overpowered)
Marks:
Mark of Health x4:
These are good for early game health so you can get those clears good early on. Most people don't combine scaling and base but I just do and it seems to work well.
Mark of Scaling Health x5
Like I said before these are good for early tank. I like to combine so you get a nice health increase around level 4-5
Seals and Glyphs:
HEALTH REGEN no questions asked, nothing more, nothing less
HEY RIOT, Where is pool party Zac?

Offense:
I always run 7 in offense for the cooldown and the extra AP, not much to say about that.
Defense
You have to run every health and health regen mastery you can get your hands on. Its necessary, no questions asked. When playing jungle I use runic blessing so lose almost no health on the first clear if you have a good leash(thats the hard part).

The build order shown above is what I almost always go with. It is the only viable option to just rush Cinderhulk, if you decide to play top with this build and take smite(which is a completely good option), you would take challenging smite, doing this will let you 1v1 anyone. You will probably notice that all of the items in the final build excluding your jungle item have a giants belt in the build, more health = more good.

First you will start w, no questions asked, then q, this is most helpful for clearing the first camps, then e, the reason you max w is for the percent health which is most of Zac's damage with this build. You have to get R at every level you can.

Flash and smite, base jungle spells

Thank you for reading my Zac tank jungle guide!
This is the first guide I have created but I will probably make more in the future. I hope this has given you a good idea on how to create an unkillable blob. Once again, Thanks

Srsly Riot 5.8 maybe?]