Roguish Archetype - Toxicologist

You hone your training on the creation of toxins and poisons. Those who follow this archetype prefer subtle death instead of the direct approach. Favoring difficult to trace means of death these rogues are usually hired as accomplices for those who work for the underbelly of the city-states. 

When you choose this archetype at 3rd level, you gain proficiency with the poisoner and alchemist supplies. If you already possess these proficiencies you instead gain expertise. 

Starting at 3rd level, when you use a potion, poison, or alchemical reagent you may do so as a bonus action regardless if it is used on yourself, an ally, or a foe. 

At 9th level, due to your intense study of the physiological properties of your victims, you gain the ability to further enhance your creations through the following means.

• You may add a poison to any alchemical mixture you produce. To do so you must possess the poison in question and it is consumed as part of it's creation. Unlike most creations the poison is active until the alchemical creation is used. When doing so, you use double the poisons worth for the materials required to infuse the poison without destroying it in the process.
• When afflicting a creature who normally has immunity to poison, they are instead resistant and gain advantage on the saving throw for the condition. If they are already resistant, it is treated normally.
• A creature afflicted with your poison, treats you as invisible for the duration of the poison or, until you successfully attack them.

Starting at 13th level, you manipulate your created poisons/alchemy to provide different effects.

• You may increase the DC of your poisons/alchemical items by 2
• You may increase the area of your alchemical items by double
• Your damaging poisons/alchemy may deal an additional half of the die rolls rounded up.
• You may make a spell infused concoction. These require an action to use regardless of features or abilities. You must dissolve a spell scroll no higher than your proficiency bonus into your creation. Doing so infuses it with the spell and any effect that requires a DC Save is set to 8+Int Bonus+Proficiency Modifier

You may add your sneak attack bonus to poisons, and alchemical creations.