This guide is for an semi-tank tyrn which will allow you to initiate team fights and absorb large amounts of damage. The reasons I'm posting this build is because I haven't seen any similar builds, and I have had success with it.

For Runes you should always have:

Greater Mark of Malice
Greater Seal of Malice
Greater Glyph of Celerity/Focus (Either is fine. I use mostly celerity because tyrn levels fast)
Greater Quint of Malice

Note: do not use Marks, Seals or Quints of furor... you need the early crit chance for bloodlust.

21/9/0 is the obvious choice. How you distribute the points is up to you.

Self explanatory. Start with brawlers gloves (which will be built into a Phantom Dancer) and 2 health potions for your jungle (or laning). Pick up berserker's greaves and rush an infinity edge. Finish off the Phantom dancer and then build a frozen mallet and a warmogs. The last item is optional I like the Atma's for the crit chance armor and the fact you'll have over 4000 Hp, also it is a fairly cheap item allowing you to quickly buy elixirs.

Other options:
Last Whisper: For Armor Heavy Teams
Thornmail: For AD heavy teams
Force of Nature: for AP heavy teams
Bloodthirster: Its that good (with your HP you probably don't need the vamp though)

I Go:
Exhaust
Smite

Tyrn is a strong jungler as he doesn't need to build a Mandred's and is usually poor in the early laning phase anyways.

Other options:
Ghost
Flash
Cleanse
Heal
Teleport

Spinning slash to close the gap, mocking shout to slow (exhaust if necessary).

Also use spinning slash + smite to steal dragon/baron works fairly well.

Don't forget to use you bloodlust stacks to heal at key times. Before using Undying Rage/when escaping with lethal DOT's.

Hope you like the guide.

GL+HF