Hello! :D
This is not my first guide here, you can check others out on links bellow. I have masterly level 5 with Darius but I've been playing him on top since season 6. Really really fun champion to play :) Why? Maybe because you win every melee matchup and can deal with many ranged ones. Maybe cuz you deal 500 damage on level one with hemorrhage and ignite alone. Maybe cuz you enter teamfights with hemorrhage and just spam R until you get penta? Yea. Fun :) But there is dark side of Darius. Bad game. If you start first 5-10 minutes bad, there is probably no coming back. Some really heavy teamfight with baron might get you up but real hard. He is useful in teamfights always but not as close as fed Darius. So don't be greedy, farm and ward and you shall win almost every macthup! :)
Link: https://www.mobafire.com/profile/poljca2-751598/content/builds

PROS

-Scaling

-Huge AD and HP

-Teamfight carry

-Decent sustain

-1v5 potential

-Easy to master

-One of the best early games

CONS

-No gap closer

-Easily kited

-Incredibly weak without hemorrhage

-Conqueror is the best all around rune to take for juggernaut build. Good for both 1v1 and teamfights, only thing that it lacks is movement speed (which can be taken care of with spells, other runes and items).
-Triumph is best option, great survivability and fights and also some extra gold on the side.
-Legend:Alacrity is great for stacking up your passive faster, but Tenacity is also a great option against CC. You COULD take Bloodline, but it's a fodder comparing to the other two.
-Last Stand is a great fighting rune, as it will increase your damage output when you are low. It's pretty much the best out of the three.
-Bone Plating is great for trades, short fights and burst survivability, but second wind is also a great option for safe laning, especially with Doran's Shield.
-Revitalize is great not only for more sustain in lane but also survivability in fights. Unflinching is also a great option against CC.

-Choose runes depending on situation! (their team/your play style/your team)

-More play options in fights (like flash combos or dodging dangerous abilities), but for chasing, usually outperformed by ghost.

-Pretty good option for safer laning.

-Useful and good with passive, great for aggressive playstyle.

-Great for both chasing and being chased, stacks good with nimbus cloak and mr boots.

Darius relies on wise item choice! So I will sort you out quite flatly what and when to buy:

-Against long range matchup:start and normal tanky later

-Against strong AD:or in start and second item AR (Dead man's, Sunfire Cape, Ninja Tabi...)

-Teamfight capability:

-Hard CC/AP:(you can't do nothing more since QSS doesn't quite suit Darius but if you really suffer and you are already tank it can be an option)

~Also don't go overboard with some item sort (too tanky can make your damage fall off or too much AD can turn you squishy) but you can't go overboard with jugger items (AD and HP items) Sterack's Gage is main item for Darius! Always take it! It grants you 73.5 AD on level 18 and is very useful in both 1v1's and teamfights. Darius also has third biggest base AD on level 18 :3 with 147 base ad and just Sterack's Gage, you already have 220 attack damage and 450 with hemorrhage! Add that to your HP increased (shielded) by Sterack's and you are all set Juggernaut with just one item! Now, don't get hyped, that is level 18 stats. That means that you should take Sterack's third/fourth item and not first or second.

All three of his abilities are OP: Q has insane area damage and heal, W damage and low cooldown and E Ar pen and grab so if you use your combo good (AutoAttack, Q, AA, E/W, AA, W/E, AA) you get full hemorrhage in 3-4 sec! All three are good so what to max? You should max Q than W and E in the end. In lane, poke your opponent with Q but look out for mana! Darius has really low mana at low levels and it can be ate really quickly. If enemy is ranged, your poke should be E+AA+W+Q because that has the biggest chance of hitting. Missing E leaves you out of options for a quite while so try to hit it every time. Also, taking Transcendence against such enemies can be useful so you don't get much harassed while your E is on cooldown. Be careful who you Dunk in teamfights. If you don't seem to be able to stack up hemorrhage in teamfights, just wait for someone to fall low and ult him since killing with ult grants you instant hemorrhage.

LIFE STEAL BUILD:

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