Hello!
My Name is Bitsch and welcome to my first Guide. It will be very short at first, but will grow as i get feedback and makes new sections.
In this guide i will go over some of Darius's various mechanics and builds. I mostly Play Twisted Treeline but this build works in Summoner's Rift too.

Darius is a melee dps with high sustain and high damage. He is a good solotop, even if the opponent team have no jungler. He just stands under tower and last hits. If the enemy gets to close he just pulls them under tower.
Many might build him with no sustain, and only attack damage and attack speed. But i find Darius to be a really good bruiser. Better to build him like a bruiser than full AD. He's not a carry.

I will try to update this guide, as soon as i learn something new about Darius, and upload some pictures of my final scores.

Pros + Good Sustain + Good Damage output + Passive DOT + OP Ult + Good at rescuing chased teammates

Cons - Slow - Good at Killstealing - Darius überrage - OP Ult - Mana hungry - No Escape tool

Core Build

Doran's Shield It gives you a bit of health, some armor and a just a little health regen. All stats that increase your sustain.

Berserker GreavesBerserker Greaves Gives you an offensive boost. Makes you more dangerous.

Frozen Mallet

Considerables:

1. Merc's Nice alternative, against heavy CC team, or heavy AP team.
   
2. ThornmailGood against Heavy AD team or fed AD Carry.
   
3. Warmogs Armor I often buy Warmogs because it gives alot of extra health. If You buy warmog then you should buy Atma's Impaler too.
   
4. Atmas ImpalerAtma's Impaler
   
5. BloodthirsterGives alot of ad and lifesteal.
   
6. Upgraded Hexdrinker Good against teams with mixed AD and AP, and Heavy AP Teams.
7. Force of natureGood against heavy AP Team. Also gives alot of Health Regen.
8. Last Whisper Good against teams with high armor.
9. Infinity Edge Good Offensive Option. Good Against them Squishes. For when you need that hard hitting AD Bonus.
10. Randuin's OmenGives the third most armor. Nice defensive touch, with 350 Health and 75 armor, and a anti AD Carry active for when they hit to fast.
11. Frozen Heart Gives alot of armor, some cooldown, and reduces the attack speed of all opponents around you

Flash is a solid choice for any champion. A great escape tool, something Darius lacks really bad. Can Also be used as a gapcloser.

A really good choice for alot of champs. If you have almost killed some1 and they got some distance, so you can't pull em back, and can't bunnyjump them, they might still be in range of ignite.

Good at slowing your opponent if you ain't close enough for a . Can easily secure kills.

Other good Spells

also a really great spell, works both as escape tool and gapcloser.If you are like me don't get this. I always forget to use it.

Great spell. Life saver. Might turn a fight.

Can be good, if you are up against a team with 5 ignites or some hard CC.