Chemist for Dummies.

I typed out this lengthy response to a new player asking for tips on chemist. Might as well post it here too.
It's made for newer players to the class in casual CTF, not competitive shenanigans. I'm also not too good at pvp myself so keep that in mind.
**** on me all you want for my ****ty guide.

General tips
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Sword - Your sword is your best friend, not your pots. The sword deals 4.5 hearts after buffs, and deals way more damage than other swords or your pots (unless enemy is buffed too).

Damage pots - These should be used for knockback purposes most of the time, not damage. They deal only 3 hearts if you land it perfectly, which isn't a lot (except against heavies).
They also help in continuing combos (comboing is easy with chemist b/c of speed and deals damage quickly).
Other uses include killing assassins (switch quickly to pot, throw it, and switch back to blocking), knocking back people chasing you, avoiding running into a heavy/pyro, and damaging ninjas.
These pots will never hurt you or teammates.
ALSO DON'T SPAM DAMAGE POTS PEOPLE WILL HATE YOU

Poison pots - Some chemists use these often, others don't at all. I find myself using more poison than damage, although I only added poison into my repertoire only a couple months ago. I use these to slow people down (damage ticks), reducing knockback, and damaging classes with lots of armor such as heavies.
If a player is poisoned, they take reduced knockback b/c of damage ticks, often none, even against Punch 1 arrows. Sadly lightning still knocks you back a lot. These will poison you and your teammates, but only if an enemy player is in range. You can give yourself reduced kb this way, which is sometimes useful.
Every poison tick also can kill vulnerable assassins, and poison is a good pot to use on them. However, if the assassin is good, it can time the assassinate, and kill you between 2 ticks (they'll still die to the next tick if the poison is still on them)

Healing pots - They heal 8 hearts each. Know how to apply them to their maximum potential (running forwards and throwing one in front of you so you run into the pot in midair and get all 8 hearts), although you won't be doing this very often in fights.
These pots, combined with regen, allow for chemist to be very tanky and a suitable class for carrying the flag.
Be aware that these also heal the enemy! So try not to use them when they're right on you.
NOTE: THEY DON'T HEAL YOU INSTANTLY! This can be a huge problem sometimes as the time it takes for them to land on the ground is a matter of life or death, because your armor is not the greatest. You also can't survive long falls if you have lots of health missing as it's nearly impossible to heal in midair.
You may need to prematurely pot if you're taking lots of damage fast. This means using a healing pot when you're only 4 or 5 hearts down, but you should judge for yourself.

Regen pots - These are your lifeline, basically. They're pretty much essential in all fights due to how fast they regen back the health.
They can also be used to heal teammates, especially ninjas (allows them to pearl freely for a couple seconds).
I find myself using more regen pots than healing, and if the opponent is not very skilled and playing a class with low armor, often a regen pot is all you need to kill them.
You also get 5, which I find to be quite excessive considering how long they last.
Ensure you always have regen in fights if possible.

"Slowness" pots - These don't actually give slowness, they give weakness and mining fatigue. Don't use them. They're not worth it. I tried and it was just a waste of mana.

Strength & Speed pots - Self explanatory.

Fire Resistance pots - Fire resistance isn't too useful, but have them against pyros so you aren't slowed down by fire tick.

Fighting specific classes
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Heavy - They're a pretty good counter to chemist due to their high damage output. If you get comboed, you're in a bad situation.
If they're good at pvp, then run you can't do much, except maybe poison them before running.
In other cases, you can choose to use poison or not. Poison eats away at their health, more so if you run away to regen some, but also allows them to combo you easily.
Use a bit more damage pots as your sword deals less than a heart to them.
Try not to ever give them regen or health on accident.
Takes a bit of practice to fight these.

Soldier - Poison hampers wallclimb a bit, is useful if they're trying to get away with the flag.
If they're good at pvp, they can kill you because their iron sword isn't terrible, but only if they combo you. Overall, you have the advantage.

Archer - They deal 2x damage to you with arrows, and apply a slowness affect on you. Be careful as 2 full power shots in quick succession can kill you easily.
Poison helps out a lot if you can get in range. Poison both you and them so they can't run and you won't get knocked back by bowspam as much. If you can land a few hits, they're toast.

Medic - If you get trapped in a web, your healing will heal them too if they're close to it. You'll also get comboed if you're stuck, of course, and can't combo them easily. You'll be drained of pots.
Otherwise, they're quite tanky but if they choose to fight they're not the hardest to kill but can put up quite a fight with their Sharpness I.

Assassin - Poison helps a lot, you are usually able to not block and kill them easily if they're poisoned (unless they can time it right), but watch out if it wears out. Damage pots are useful too. They should not be too much of a threat, but make sure you don't die to them comboing you normally with their sword as that can sometimes deal a lot of damage.

Chemist - The chemist 1v1 is my favourite fight in all of CTF. It's really fun and the tide can turn quickly because you both don't have instant healing, but do a lot and take a lot of damage. Try to get close to them if you combo them so you can use some of their healing so you don't waste yours, and try not to heal them. Poison can help a lot or bit you in the ass.
Everyone plays the class differently, so every fight is usually different.
Practice practice practice!

Elf - Poison is good against preventing them using their wind element to continue combos or escaping.
They may have really weak armor, but their sword is very strong. A couple of hits can easily kill you, plus they have wind element to continue their combos. Their shield can also deflect potions back at you, but usually fights are too quick for that kind of thing.
In other words, combo them and don't be comboed.

Engineer - With your high health pool, engineers are no threat. A regen plus one health is enough to take out a turret, but always go for the cake first. Since engineers are weak armor-wise, they're no threat if you can get rid of the cake. Chemist is one of the best classes to kill them b/c of high health pool and quick bursts of damage. Just watch out for the turret and heal a bit prematurely.

Mage - The frequent knockback on their spells can knock you away from your pots, sometimes completely (lightning). Poison is good at preventing them from running away, if you can get close enough. Chemists stand a better chance than most classes, but still not the greatest.
I don't have too much practice against mages. I usually avoid them.
Just try to get close to them. You'll be drained fast though.

Necro - A well placed healing pot can easily take care of a horde of mobs, avoiding the weakness status effect that negates your strength.
Necros themselves are pretty tanky and have decent damage output, so they can put up a fight if they're good, but you should have the advantage if you're not overwhelmed by the mobs tanking all of your hits.

Ninja - 3 hits will kill you, 4 with regen. Be alert at all times, and when you first realize you're being killed by a ninja (after first hit usually), I would recommend immediately throwing down a healing pot, otherwise they will kill you before the pot lands. Use a damage pot to break their combo, and hit them twice (2 sword hits + one decent hit with a pot deals 10 hearts to them). Make sure you have regen on you as they will sometimes be the one extra hit you need to live.

Pyro - You deal huge amounts of damage to them, they do huge amounts of damage to you, but you don't have instant healing. Usually a coin toss if the pyro isn't the greatest but if they're good you're quite literally toast. Use your damage pots to knock them back and mess up their hits, but poison is not a good idea. You usually can't heal fast enough over their 3.5 hearts of pure damage if they hit you a lot, but unlike with ninja, pyros have some armor and healing so you can't just hit them back and hope for the best (I guess you could but less likely to succeed).

Gameplay Tips
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Capping - I cap with chemist a lot. It's quite tanky in the flagroom and you have a lot of resources.
Take routes with not that much open area, and some falls that deal a little bit of damage, as regen easily heals that back. Damage and poison can be thrown behind you to slow down any people chasing you. You'll be running into a lot of ninjas, so practice against those.

Defence - Throw down poison to make their escape harder. No matter what class they are, this usually helps. You deal quite a lot of damage and move faster than them, so defensive chemist isn't too bad of an idea. You can die quickly though, which isn't too good for a defensive class when you're focusing on the enemy and not your health bar.

Roaming - Chemist is pretty good for roaming. You can take out weaker classes easily and remove pesky engineers.

Closing statements
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Chemist is one of the better classes for killing other classes, with not too many weaknesses. The large quantity of supplies allows you to fight a lot of people without needing a medic. It's also used for capping and even defending. If you're good with the class, it's the go to class for everything. Can't kill a player? Chemist. Want to cap? Chemist. Want to get lots of kills? Chemist. Want to defend? Maybe not chemist, but it's still viable. Chemists can handle lopsided fights like 2v1s or maybe 3v1s if the opponents aren't the greatest.
However, it takes a LONG time to master the class, way longer than any other class except for elf. Everyone also plays it differently, some use poison, some use more pots than others, some focus on using the sword, you get the point.

 

Boosting my 70 in English.

 

On point.

 

“Chemist.” Wikipedia, Wikimedia Foundation, 22 Nov. 2017, en.wikipedia.org/wiki/Chemist.