PROS + Very strong early + Great engage and peel tools + You have a big impact on the game + Very fun to play Nautilus is a fantastic engage support with a fairly easy kit to play with. He is quite forgiving and great for someone who is trying to learn to play engage. He has a lot of base damage in his kit with a lot of CC. He even scales pretty well into the late game.

CONS - Missing hooks can be very punishing - Might struggle with weak adc - Has no sustain - Gets outscaled by enchanters Nautilus can be poked out of lane in poke matchups. His shield will reduce your damage taken a little, but generally won't be enough. Therefore you need to learn to push your boundaries and engage early before you or your adc loses too much HP.

RESOLVE

Aftershock allows you to buy more space in the frontline whenever you go in for either a trade or a fight in the lategame. It's especially usefull if you're playing against another engage support in lane.

Shield Bash gives you some more resists and more damage on your next AA whenever you use your Titan's Wrath which is always a part of your combo. If you'd rather play more deffensively then Font of Life gives your team slightly more sustain whenever you CC an opponent.

Second Wind when you're in a poke lane, Bone Plating when against engage and more bursty botlanes. If you're not too concerned about the lane matchup then Conditioning gives you some nice tanky stats later on in the game.

While Unflinching doesn't give a lot of stats it's still decent for someone like Nautilus who is going to be quite deep most of the time. Overgrowth is decent if the enemy team doesn't have any CC.

INSPIRATION

Hextech Flashtraption and Cosmic Insight both allow you to be more active with your Flash which is great for Nautilus. Biscuit Delivery is a decent choice though if you think you don't have a lot of options for Hextech Flashtraption and will need some more sustain.

Runeshards are going to depend on what items you think you want to go for in the game. If you want to go for more peel items then you can go for Health Scaling instead of Movement Speed, but I think Trailblazer and Movement Speed goes really well together. Tenacity and Slow Resist if needed.

INSPIRATION

Glacial Augment is fantastic against ranged botlanes as it will make it harder for them to kite away from you and your adc will also take less damage from those affected by it.

Hextech Flashtraption can catch your enemy off guard and lead to more picks.

Biscuit Delivery gives a decent amount of sustain and mana regen in the early game.

Cosmic Insight allows you to be more active with your Flash.

RESOLVE

Unflinching gives some added tankiness and then it's either Second Wind if you're going to be poked or Conditioning if you're not too worried about the lane.

If you want to go for more peel items then you can go for Health Scaling instead of Movement Speed, but I think Trailblazer and Movement Speed goes really well together. Tenacity and Slow Resist if needed.

Speedy roams Trailblazer is a great item as it gives you and your teammates movespeed to cross the map faster.

Stickiness Zeke's Convergence creates a slowing field around you which makes you sticker and harder to kite away from.

Great defensive item Locket of the Iron solari is still a fantastic item that helps you protect your teammates. This is just a fantastic item that you should always consider when you need to peel more.

Chivalry isn't dead Knight's Vow gives you great stats for the cost and helps you peel for your fed teammate and keep them alive (and get some healing for yourself as well).

Anti-heal If the enemy team has a lot of healing this is a great item, but in a pinch Bramble Vest acomplishes the same thing for much cheaper.

Anti AD item Frozen heart is a really cheap tank item with great stats for the cost and the added benefits of the passives make this a really compelling item when facing multple AD or AA based champions.

Anti AP fight item Abyssal mask gives you a lot of magic resist and health for its cost. It also enables you and your ap damage dealers to do more damage.

Anti AP poke item Kaenic Rookern is a great tank item when facing a lot of long range poke. It's a bit expensive, but it's well worth it.

Single damage threat Anathema's Chains is a decent choice if the enemy has one super strong member and four bots/tanks. It also reduces their tenacity.

Great objective vision control Vigilant Wardstone should always be your final item if you get this far. It gives you more wards on the map, more control wards in your inventory and some nice bonus stats as well.

Staggering Blow Short CC on AA. Your passive allows you to root an enemy when you auto attack them every 6 seconds. Try to apply to multiple people in a fight.
Dredge Line Anchor or hook? Your primary ability on Nautilus. Throw out your anchor and if you hit an enemy you pull them halfway and you fly the rest of the distance towards them meeting in the halfway point. (If you hit a wall you will fly towards it and have the cost and cooldown refunded by 50%)
Titan's Wrath Shield and bonus damage. Your W is a shield that also gives you a "mini-tiamat". (It works as an auto attack reset allowing you to instakill wards placed in front of you.)
Riptide Big AOE slow. This ability causes three shockwaves to erupt around you, dealing damage and slowing enemies. (Can be cast during your Dredge Line to avoid the cast animation while escaping.)
Depth Charge Point and click AOE knock up. Your utlimate ability sends out an undodgeable knockup that will chase your target and knockup enemies it passes under.

PASSIVE ABILITY

Staggering Blow ✦ Your AAs will root your target for a short duration with a cooldown of 6 seconds per target. Try to hit multiple people in a fight so you can get the CC and bonus damage, but don't overextend and leave your teammates alone or put yourself in too much danger.

Q

Dredge Line ✦ Your Dredge Line's hitbox doesn't quite match what you see when you aim it. It actually has a "bloom" effect on the end often reffered to as "lollipopping" which describes the shape the hitbox actually has. This means that you can hit champions standing behind minions or walls if you aim slightly next to them.

W

Titan's Wrath ✦ Your W works as an auto attack reset meaning that you can kill wards alone if they get placed in front of you. ✦ It does AoE damage when you AA which can accidentaly kill minions in lane which can lead to a very upset ADC.

E

Riptide ✦ Riptide has a short animation that can be started as soon as you throw out your Dredge Line. This way you can either easily do damage faster to the enemy you're hooking in or have your Riptide slow the enemy chasing you while you use your Dredge Line on a wall to run away without slowing down.

R

Depth Charge ✦ Sometimes you will need to make a judgement call whether you want to use your Depth Charge on one singular champion or a large cluster of enemy champions. I wouldn't say there is a correct way to use it as every game is different so try to keep an open mind on how to use your ultimate whenever a fight arises.

This chapter will have random information and tips regarding that didn't fit into the guide elsewhere.

Runes:

If I don't need the Tenacity and Slow Resist shard should I take Flat Health or Health Scaling? Well the Health Scaling will give you more health level 7 and onwards, but I don't think that's very relevant on Nautilus as you will be fighting a lot early on and because you're playing support you aren't going to get a lot of XP from waves so scaling stats will be less valuable anyways.

Items:

The damage taken from Knight's Vow when redirected from your ally to you will proc and waste your Celestial Opposition so try to keep that in mind as you have to be out of combat for 20 seconds for the shield to come back up. It also deactivates your Mobility Boots even if the damage is only from minions.

When in a fight without your Knight's Vow target (whether they're dead or just not in the fight) you should try to change your mark to another teammate. This way you're still getting value from the passive. Another thing to remember is that the target doesn't have to be your adc. If your adc is super behind while your midlaner is smurfing you should change priorities. Don't get stuck in the mindset of having to support only your adc!

Solstice Sleigh is not a heal it only gives bonus health, so it is not affected by grievous wounds or heal and shield power. Think of it as a mini Wild Growth.

Abilities:

If you use Dredge Line on a wall then 50% of the cooldown and mana cost will be refunded.
If you're being chased then you can use that to your advantage and hook a wall in the direction you're running and use your Riptide then you will be dragged away towards the wall and the enemies chasing you will be slowed by your Riptide from your previous location.

Check out my other guides if you'd like!

The chain warden of botlane
Warm hugs for everybody!

Special thanks to jhoijhoi for their great guide to coding.