This is my crossover guide from playing Dota, HON(gladiator), and Dota 2. I'm completely awful at grammar so you'll have to bear with me during this guide. I hope you enjoy it, and if you see any corrections or things you'd prefer changed I'll look at them and consider updating the guide to better reflect a strong Kunkka.
The initial items are fairly basic, and are also in the shop as a recommendation.
The 2 gauntlets of strength really help bump up your early damage and health as well as Regen, you can supplement with branches if you prefer, since you could have a double stun team and need the extra mana, but i prefer the extra gauntlet simply because it makes your tidebringer attack that much stronger.
The tango, healing salve and mana pot are there just for that.
Power boots are a must of course. You have to have speed, the str bonus, and the attack speed helps when your chasing people down after a torrent or x marks the spot. The multiple bracers and vanguard help with the tankiness, just giving him more survivability, while the bracers also help with his low intell gain from levels that you're going to need with mass torrents and x marks the spot.
The Crystalis is extremely useful for tidebringer. If you catch an ult on it, and the subsequent daedalus, it goes into tidebringer unleashing large crits in a massive aoe, making this hero extremely dangerous in teamfights and extremely good at farming lanes and jungles. Lastly the helm of the dominator further increases his survivability by giving healthsteal and the +5 armor bonus.
Daedalus is just an obvious upgrade to Crystalis, making Kunkka deal that much more damage, and the satanic and heart are to further increase his tankiness to the maximum level so you can take hits and deal out mass tidebringer attacks in fights, making kunkka a hard carry with tank skills. The Shadow blade is explained in the skills section and is the crossover i took from hon, also assists with getting to and out of fights faster if necessary and makins Kunnka extremly extremely handy in fights as well as ganks.
This skill build is for aoe damage and mostly for a solo lane.
Your maxing out tidebringer so you can keep the damage on your opposing hero in lane. If you can, play it smart against ranged opponents. Every-time your c/d comes up, run up and slash a creep making sure that the opponent is directly behind it, so you do damage to him as well, then run backwards to stay out of his range.
There is a range to tidebringer, but the tidebringer is fairly large.
Once you have level 2 torrent at level 4, try to wear down your opponent to about half or hopefully a little under half health. Once there, position your torrent touching him and slightly behind him, so if they try to run they get hit anyways, then throw out another tide bringer right on them, or at the creeps near you with the opponent behind. If they run, which they should since they're very close to dead, chase them and try to torrent where they're running when the c/d is up, if not, just keep chasing and once the creeps get near, attack them with the opponent behind again and it should kill them. Easy first-bloods with this hero since Tidebringer is extremely op early game.
I'm assuming for mid game your around levels 8-16.
You'll have all your skills set, including your x marks the spot at level 2 which is very useful for ganking and that's what Kunkka is all about. At this point you have at least power boots, and vanguard. So your a little beefy(high health) do decent damage, and have a good attack speed.
I'm going to make two scenarios here, and what you should do in each, it should b all around.
Scenario One, the Team Fight:
Hopefully you have some aoe fighters with you to keep the damage up with your ultimate(Ghost Ship) and your torrent landing. Throw a torrent as the initiator, right on the heroes in the front, it stuns and slows them, making it hard to get away. As soon as you throw the torrent, click on your ghost ship to be just in front of the enemies in the back, the ghost ship always goes forward a bit of an extra distance from what you selected it, so keep that in mind as you position it. Try to get the ghost ship to go through your teammates as it "delays" damage(makes your damage halved for a short time, but then it will all come back to you) and speeds you up as well. When the torrent lands the ghost ship is already on it's way, attack the first hero/creep in front of you to effect tidebringer, then use an x marks the spot on anybody that tries to get away, at full level 4 that will last for 4 seconds on delay,but since we're at level 2, throw another torrent down if it's off c/d yet and it should b almost immediately after x marks the spot affects the enemy hero, where you can again slash with tidebringer and with the rest of your teammates damage break down the last of the opponents.
With the above scenario in mind, I'm going to assume you know how torrent/tidebringer and ghost ship/x marks the spot work so we'll gloss that over.
With a stunner, have your stunner hit the opponent first, throw a torrent down as soon as you see it, and a ghost ship if you have it right after just like the previous scenario. Run up and tidebringer the opponent and x marks the spot right after. Pretty much easy-mode after that.
For late game, try to time your shadow blade. Torrent the opponent, then shadow blade up and attack as they're landing. The first attack out of the ghost walk will add 150 damage, plus if you have Daedalus it stacks with the crit and that's a whole lot of damage, x marks the spot after, and if they try to run and it's narrow, throw a ghost ship at them. The Cooldown is fairly short and immediately after you can torrent and ghostwalk tidebringer yet again for another easy kill.
Overall Kunkka is one of my favorite heroes in any game ever.
He's just easy to use, easy to understand, if you get the right items and land your torrents and ghost ships, it's game. He's great vs. invis heroes because his tidebringer hits them if they're in range as well, and his x marks the spot with a torrent obviously isn't stopped by that hero invis'ing. As for push teams, if you throw chen's creeps with broodmothers creeps with nature's prophets creeps at kunkka, 1 torrent and 2 tidebringers is a lot of money, and that can be done within 4 seconds. Love this hero and i hope you do as well.