An entire department designed around getting close to other people.
Kudzu: Botany's favorite shuttle caller. You can splice all sorts of plants into kudzu, but frankly even unmodified kudzu is enough to piss everyone off. Modify the genes enough and you will end the round. Experiment and destroy everyone's hopes and dreams in increasingly more exotic ways each time!
Nitroglycerin: An explosive that can be mixed using organic chemicals from plants. It's portable, stealthy, and is significantly more powerful than typical Water + Potassium, although not as powerful as toxins.
Organic Poisons: There is a host of rare poisons and chemicals available from plants. Even more so if you get access to an Exotic Seeds crate. Use these to fill syringe guns, poison food, make blunts, sabotage cryo, any reagent injection method you can think of. Some of the more interesting chemicals like mint toxin, hemocyanin, vapor salts, and cyanide are all unique to botany. If that wasn't good enough for you, your different plants mixed together can give you access to almost every chemical available at chemistry.
Organic Poisons: Only One Cure: Botanists have access to Ambrosia Cruciatus in their uplink. The toxin it produces is arguably one of the most horrific and hilarious things you can poison someone with, turning your target into a gibbering, stammering, retarded wreck of a human being, the only cure for it is to kill and clone them. It takes some time to metabolize, so 7 or 8 units should be enough.
Organic Poisons: Exotic Seed Crates: A score of unique plant properties such as stinging, injecting, vines, juicy, carnivorous, hematophage and many more, not to mention the rare reagents inside exotic seeds, such as Mint Toxin, (Advanced) Mutation Toxin or Defalexorin (Heartbreaker Toxin). Lots of possibilities in those crates.
Death Nettles: Why buy an e-sword when you can grow one? Jacking up the potency on Death Nettles can net you a melee weapon capable of husking people in a few hits. Best part? It does burn damage. Death Nettles have a chance to do double damage but their damage halves with every use, so dispose of your current one after 3 or 4 uses. Your plant bags can hold up to 50, you can afford it.
Novaflowers: Death Nettles' spicier cousin. Does slightly less damage than a Death Nettle at the same potency, but heats up the victim A LOT instead, easily reach 4000°C body temperature with some hits. One or two hits and your victim is guaranteed to go down due to the constant burn damage they'll get.
Bananas: The most evil holiest fruit, especially in the hands of a clown. Give them hundreds and help your new friend scatter peels on every tile. Bonus points if you give them Bluespace Bananas instead, since those teleport the shoes of whomever slipped on them, distance depending on potency.
Bluespace Tomatoes: You don't need access if you can teleport. Bluespace Tomatoes teleport you within a radius that depends on potency just like a Blink spell would. This allows you to teleport to any area, including teleport jammed areas (though it's harder to blink there). If thrown at someone, they'll (usually) teleport instead. Bonus points if you spliced Blue tomatoes into them as well, since each splash lubes the tile it landed on. Extra points if you spliced Glowshrooms or Blood Tomatoes for radium or blood splashes on the floor.
Spliced Tomatoes: Tomatoes splatter on impact, causing the victim to absorb any chemicals inside the tomato. Splice with ghost peppers to create stun bombs. Use Death nettles to create acid bombs. Angel Tomatoes will cause a delayed murder. The sky is the limit with these! Exotic seed crate chemicals can make these MUCH more deadly, such as sliming people with thrown tomatoes.
Amauris: If your shift is lucky enough to have a xenoarch find and bring these to you, these neat little things have the NOREACT property, which means chems inside only react on biting, in most cases… except for the above mentioned tomato splicing. Be sure to PURGE morphology from them onto this plant so you actually keep the smoke chems. Once ready and harvested, be sure to aim at your targets mouth or head for the chems to actually react. An example test with phenol splicing usually means that successfully hitting them with these is equal to a pacid smoke grenade. Very effective for murderbone. (unless their head or mouth is covered with a good permeability-proof mask or helmet, which usually makes this hit or miss. If they're wearing a biosuit, don't even bother.) Works just as well with EMPs or explosions, try everything!
Dude WEED lmao: Smoking Ambrosia blunts will give you chems over a long period of time. You can create an amazing healweed by splicing Ambrosia Deus into Ambrosia Vulgaris, allowing you to go on drugged up rampages. Moreover, crops act as a 100 unit container and you can syringe 100 units of ANY chem you want into a crop. Give people a blunt with 100 units of welder fuel and plasma and watch as they blow their face off upon lighting it. You can get plasma from Plasma Cabbages.
Botanical Atmospherics: Mutate a plant enough, and you might get lucky and create a plant that spews gasses. It can be any gas from oxygen to plasma. The amount scales with Potency and will start spewing as soon as the seed is planted. You can plant these all over the station or put a hydro tray lid up over it, then wrench the hydroponics tray into the distribution pipe to democratize the N2O. If a plant has vines, the vines will also emit the gas.
Clown Pods: If you can somehow get your hands on this admin only item, and know how to dupe your seeds, you can end the round by turning the station into a circus.
Hell Ramen: A super spicy reagent that very rapidly heats up your victim when consumed, possibly killing and husking them. Can be manufactured by mixing some capsaicin into hot ramen or by making Haunted Jam, a dangerous delicacy that contains a decent amount of hell ramen. Slip a double portion of the stuff into the nicer looking dishes for a hot surprise!
Serving Man: A space station classic, the gibber in the kitchen backroom. Strip your victim (dead or alive), drag them onto the gibber, and turn it on. Moments later, they will be nothing but meat and impossible to clone. Make sure to turn them into delicious burgers or chili for their former colleagues to enjoy. Ground beef not your thing? You can use the food processor to turn them into chicken nuggets, but only if they're wearing a chicken outfit. Steal one from the theatre next door!
Kinder Eggs: You can hide any small or tiny item inside a watermelon or a lasagna, then eat it out later! Perfect for emags, or pacid grenades.
Obesity Epidemic: Inject corn oil or deep fry your food to make most of the crew fat. Unlike other methods of poisoning your food, this is unlikely to get you lynched (you're just doing your job, after all). Once your target is waddling nice and slowly, stuff your special mint from the back room into their mouth and watch them instantly gib. The mint only gibs fat people, in a reference to Creosote from Monty Python's The Meaning of Life. You can also grind it to inject the mint toxin into a food item. The only way to get more mint toxin is either a random chance in Sweet Sundae Ramen or getting lucky with exotic seeds. You can roll more chances per Sweet Sundae Ramen (up to 7 chances per ramen!) if you Water + Potassium or smoke out the reagents inside the ingredients before completing it.
Meat Cleaver: The meat cleaver is a highly desirable item. As robust as an e-sword and much less obvious, this can seriously ruin someone's day when you whip it out of a backpack or your apron's suit storage. Better yet, it quickly disposes of bodies into meat you can simply grind up or eat. Worst comes to worst, throwing it can stun people but you should probably only do this if you're about to be killed anyway - otherwise you'll run the risk of having it turned against you. Aim for the head for a decent knockout chance as well.
Cook Along: A fun yet morbid project could be to knock your target out and sneak them into your back room with a bottle or five of clonexadone and an IV stand. Strip and strap them to a chair and make all their blood into meat while they watch. Disabling cameras is advisable, since this would be an exceedingly slow process.
Heartburn: The Chef's Special Sauce is a guaranteed instant kill that will be a blatantly obvious death, as it is instant (after a time delay) and doesn't cause damage, just death. Any decent doctor will immediately recognize Chef Sauce and report it accordingly, so prepare for that. Chef Sauce is more often than not used by non-chefs to poison the chef's food, so you can claim that the food wasn't poisoned by you. Of course you didn't poison the food, you'd be the first suspect if you were a baddie! Once discovered, “dispose” of the poisoned food by grinding it, extracting the Chef Sauce and injecting it into more food.
Beating the Competition: The “Does Not Tip” syndicate uplink item is especially useful for chef to insure that he gets a steady flow of customers.
Potent Hams: Potent Ham unleashes an EMP blast on bite. Why not eat one right next to a crewmember who has assisted organs or limbs? Be aware that this EMP is rather small (but strong) when compared to Uranium + Iron mixes and requires fairly exotic ingredients.
Karmotrine: Drinks using Karmotrine have a wide variety of hilarious side effects. Take a peek at the Drinks guide. See if the Gods will TC trade you some Surik seeds and have botany grow them for you. Spiders creates spiderlings when consumed, which can quickly turn into a SPIDERLOOSE event, Suicide causes relentless vomiting and Gravitational Singulo (and Gravitational Singularitea) creates an actual Singularity if a sentient imbiber metabolizes more than 250u, letting you singuloose without engineering nor science access. You can mass produce Gravitational Singulo by splicing Surik into Bluespace Tomatoes or vice versa.
Roofies: The Neurotoxin drink will completely stun and silence someone upon consuming. Perfect for kidnapping related gimmicks or for disposing of the more problematic crew. Amasec is a close second if you can't get your hands on sleep toxin, since it'll stun but not silence.
Dive Bar: It's a hard life being a syndicate agent. Why not turn your bar into a hive of villainy and scum? Refuse to serve security members and make the place a hideout for greyshits and syndicates. Turn the bar red with a big S symbol and offer services to the less reputable crew such as stowing their gear, ID changes contraband trading, and SE/UI syringes from genetics for appearences. Every villain needs a place to lay low.
White Glove Society: Use the backroom to kidnap people and harvest their blood and organs to put into drinks and as appetizers. Consider that the bar storage room is usually directly below or next to maintenance, its really easy to jump people sneaking through there if you have the wallhack goggles. Be careful about noise or kill people while there's patrons at the bar who don't notice, the choice is yours! Use codewords to get syndicate patrons involved and run a little organ harvesting rink of sick freaks!
Word On The Street: As bartender, people actually stop and talk with you. You can use this to gather interesting information about the round while also spreading some information yourself. Start building distrust between the greytide and security. Maybe you totally saw your target holding an emag.