Juggernaut is one of the most popular carries of all time. He has versatile item choices, high base attack damage, awesome attack animation, can fight either early or go to the late game. Though he has mana and survivability issues with his low stats growth, weak against high PD and BKB-piercing disables, single-target based without mobility abilities.

He conceptually fits almost any meta and any draft and is determined by given "numbers" (CD, stats, etc).
Good against heroes that rely on abilities with debuff or MD (Zeus, Batrider, Phoenix, Tinker, Invoker), heroes whose spells you can dodge or dispel their abilities (Kunkka, Gyro, CM), squishy heroes that like to split-push alone (Tinker, NP, Zeus).
Goes both ways against heroes and line-ups that don't come online early, but against PL it's 70/30 or even 80/20.

Good lane matchups are against Batrider, Clockwerk, NA.

He is best in combo with some lane pos5 (Lich, Grim, WD, Jakiro), good with supports with disables to set up kills with Q (SK, Veno, CM, Rubick, Tusk, SS), heroes that can sit behind you and are able to counter-initiate (Centaur, Earth Shaker, Batrider, ET, NA), heroes that can spam enemy away while you are sieging (Zeus, Tinker), heroes that can buff Jugg's damage (Magnus, Ogre-Magi, Slardar), heroes with summons or high HP heroes that can abuse HW (Chen, BM, NP, LD, Centaur, DK.

Bad against hereos with spell immunity piercing disables (FV, SB, Axe, LC, Slardar, Beastmaster, Batrider, Tusk, Bane), heroes that will outscale you if you can't pressure them in the early game (AM, Spectre, TB, Medusa, Morphling, AW), heroes with high amount of PD, especially burst (Tiny, Clinkz, Drow, Ursa, Weaver, Lycan, TA), heroes that are strong against R due to summons of their abilities (Morph, Lycan, Weaver, Brood, Visage, Sven, LD, BM, Omni, Meepo, TA, Void, PL), heroes with saving abilities (WW, Dazzle. Oracle, OD, Io, SD), heroes with instant disables can cause issues (Lion, SS, Rubick).
Slardar and WR are very nasty.

Bad lane matchups are against Axe, LC, NP (both ways, but still)

Bad with greedy heroes that want to farm a lot (NP,TA, Medusa, Alch, Brood), defensive heroes that lack disables (Io, Dazzle, Omni, Oracle).

Laning stage.
Things to consider when judging your approach on enemy hero, what is his:
- armor;
- base damage;
- move speed.
Harass pos3 and get CS. Due to Jugg's high base attack speed and crit paasive you want to quickly hit enemy 1-2 times and back off to win the trade. You don't want to go for kill if it ruin creep equilibrium, but if the lane is pulled enough or equilibrium is already messed, you can go, kill and then pull the creeps back. Be careful to use healing ward not to ruin creep equilibrium, but make it still affecting you. Make sure you have HP and MP to be agressive around lvl 6. Being a threat to the enemy hero heroes also increases your farming potential.
Your farming patterns are pushing out the wave and farming the jungle with Blade Fury and HW.
When enemy harass you a lot and you are not able to farm anymore it's called "inefficient interaction" (because you can't spin the lane (they will chase you down) and you also have to spin to actually lane), when you get than feeling, it's time to leave the lane.

Early game.
Be careful when using Q openly on lane. If enemy knows it's on CD, they may try to kill you.
Your main goal is to farm to get BF as fast as you can. Your power spikes are lvl 5, 6, 7 and every time you get a core item.
4,3k NW by 10 min.

Pushing.
When pushing towers with your team make sure to last hit creeps in that lane. Use you HW in the way that affects the creepwave and your teammates.

Ganking.
You shouldn't be looking for ganks, but if you see a temmate getting dived and you have your spells ready, TO in to clean up.

Mid and Late game.
In a good Jugg game, your main goal is to split-push and farm.
In a bad Jugg game -fight early and try to finish the game asap.
Your power spikes are your new items and lvls of your ulti.
After teamfights when enemy heroes are missing, bully others out of farm.
You are strong PRIOR using your Q, when it ends, enemy will try to finally punish you.
7,1k NW by 15 min.
10,5k NW by 20 min.

Tormentor.
You can solo it with R when you get Manta and Mjollnir.
Your even earlier with teammate.

Ganking.
Jugg offers great solo-kill potential. If you can't get a solo pick-off, ask your temmates to set up a kill.

Roshing.
Jugg can solo Roshan with W, but it is better if someone tanks him for you.

Split-pushing.
Jugg is a great splitpusher because he can escape with Spin-TP and if someone comes to defend you can always kill him with Omnislash.

Teanfighting.
Try to kill supports first, maybe with Blade Fury (it's often hard to get awways if you haveused it earlier though), and save ulti for core heroes if possible. It is good if you will be able to kill 2 heroes with one ulti. At tthe beginning, you may have to use HW. Sure, it is better to save it to use later in the fight, but look to sustain your team.

Going highground.
You are every strong at it. Especially if there are no Tinker or KotL there, but even against them, you can just spin and hit towers. HW wil help ypu and your team to sustain. You also can potentially jump on a hero out of position.

Defending.
You can split-push and force someone back. Wrap around and Omnislash enemy team's backlines. Wait for your team to initiate and follow up.

Greetings, thanks and shoutout to SMD, CCnC , Sogarde, Yamsun (Game-Leap), BSJ and Ueio.
Enjoy!

Emperor, Russia.