Rogue Archetype: Infiltrator

Get in, get on with it, get it over with, and get out. Got it? Good. As an infiltrator, you specialize in getting into, or out of, anywhere, using any and all tools at your disposal. Sure, you can pick a lock. But sometimes you need to scale a wall, dig a tunnel, pry open an impossible-to-pick door, or even make your own door through solid walls. Whether for a heist, a prison break, a smuggling operation, or any other number of jobs with varying degrees of legality, a good infiltrator is in high demand, among thieves' guilds and adventuring parties alike.

Alchemical Keys

Starting at 3rd level, you gain proficiency with the alchemist's supplies. If you already have this proficiency, you gain proficiency with one other artisan's tools of your choice. Using the alchemist's supplies, you are able to craft various compounds, listed below, to help get past any barrier. At any time, you can take an Action to craft a compound from the list; each compound takes five minutes to create, and the number of compounds you can create per day (between long rests) and carry at one time is equal to your Proficiency Bonus. Each compound counts as a Tiny item, and is expended once used. You decide what form each compound takes when you craft it(a mercurial liquid in a glass vial, a sphere of hollow tin with reagents inside, etc.). You can use an Action on your turn to use one of your compounds; you decide as part of your Action if the compound activates instantaneously, or at another time within your turn (after being rolled down a hallway, upon impact with a hard surface, etc.) If a compound requires a creature to make a saving throw, the DC is equal to 8 + your Intelligence modifier + proficiency bonus. Once created, any compounds not used by the end of your next long rest are rendered inert, and are no longer usable.

Cacophonous Compound. You create a substance which releases a series of harmless, small explosions, which create loud bangs and bright flashes for 1d4 rounds, perceivable from up to 80 feet away if unimpeded. Any creature which begins its turn within 30 feet of where the compound is activated must make a Wisdom saving throw, or be distracted. A creature distracted in this way has disadvantage on attack rolls, and any Stealth checks they may detect have advantage.

Catalysis Compound. You create a substance which creates an electrical current when agitated, which can be done as part of the Action when you use it. This current deals 2d8 lightning damage in an area equivalent to 1 foot-by-1 foot, or a 30 foot diameter if used in water or another highly conductive substance, and polarizes locks or any other metals it comes into contact with, causing them to push away from each other. If the damage dealt matches or exceeds 12, any non-magical metallic lock in the affected area opens. When the compound activates, it releases a flash of bright light which can be seen up to 120 feet away if unimpeded.

Caustic Compound. You create an acidic substance which can cover an area equivalent to 1 foot-by-1 foot. The affected area takes 3d6 acid damage if it is organic or made of an organic material (wood, rope, etc.), or half as much if it is any other substance; it has no affect on stone, glass, or magical items.

Clinging Compound. You create a viscous and highly elastic substance with great adhesive qualities which last for 1d4 rounds once activated. When applied directly to boots or gloves, any creature wearing them has no penalty to their climbing speed, and any creature ‘adhered’ to a solid structure or object by the compound falls up to 50 feet at half-speed, ignoring any damage they would take from that fall. Additionally, any creature which unwillingly touches the compound must succeed a Strength saving throw or be Restrained for the duration; a creature affected this way can use an Action on their turn to repeat the saving throw.

Concealing Compound. You create a substance which releases a harmless, odourless, thick cloud of smoke, obscuring an area in a 20 foot diameter sphere from where it is activated. Any creature which relies on non-magical sight is considered Blinded while within the area of effect, and creatures outside of the area cannot see into or through it. The cloud spreads around corners, and lasts for 1d4 rounds, or until a wind of moderate or greater speed (at least 10 miles per hour) disperses it.

Concussive Compound. You create a highly flammable, explosive substance which does 1d10 thunder damage plus 1d10 fire damage in a 5 foot radius from a point where it is activated. Any creatures within this radius must make a Strength saving throw (DC 8 + your Intelligence modifier + your Proficiency Bonus) or be pushed 10 feet in a straight line away from the point of explosion and knocked prone; on a successful save, the creature is not pushed, and takes only half damage. Any unsecured items in the area are immediately pushed away. If the total damage matches or exceeds 15, the resulting explosion creates a 3 foot-radius spherical hole at the point of detonation, excepting in materials like mithral and adamantine, and magical items. No matter how much damage is dealt this way, the sound of the explosion can be heard up to 150 feet away if unimpeded. The compound must be primed and ignited directly by its wick, or other source of heat, which can be done as part of the Action to use the compound; an unprimed concussive compound cannot be activated (ex. an unprimed compound carried by a creature in the area of effect of a fireball spell would not detonate). When ignited by its wick, you determine how much time passes before it detonates, from instantaneously up to 1 minute (ten rounds).

Coverage Compound. You create a substance which produces a rapid-growth wall of semi-opaque crystal to form on the spot where it is activated. The wall is 5 feet high, 10 feet wide, and 1 foot thick, and you determine its placement when activated. Any creature behind the wall benefits from cover, and can also attempt to Hide behind it. The wall lasts 1d4 rounds before it naturally collapses.

Crystallizing Compound. You create a substance which reduces temperatures to the point of extreme fragility. The compound is effective in an area equivalent to 1 foot-by-1 foot, and does 2d6 cold damage. The AC of anything affected this way is reduced by 5, and the next time it takes piercing, slashing, or bludgeoning damage, the amount of damage dealt is doubled. This substance is effective against non-magical, common stone and metals, but wood and other objects made from organic materials are not affected by the additional effects beyond the initial cold damage.

 

Fight Or Flight

Also at 3rd level, you can weaponize your compounds against your enemies. As an Action, you can activate and then throw one of your compounds up to 40 feet. If the compound is one which deals damage, treat this as a ranged attack. You are considered proficient with your compounds as weapons when used in this way. 

Finding The Flaw

You have gotten into and out of enough places you weren't supposed to be to spot the best entrances and exits quickly. Starting at 9th level, you can use a Bonus Action to make a DC 15 Perception check of a structure, area, or barrier; on a success, the DM tells you the best weak point to exploit in order to bypass it, though not how to exploit it. The DM does this in the form of a short statement, such as 'the northwest wall', 'a metal grate', or 'a weak foundation’, and you gain advantage on your first skill check used to exploit this weakness (ex. a Stealth check to slip unnoticed past a guard, an Athletics check to scale a wall, etc.). You can use this feature a number of times equal to your Wisdom modifier (minimum of one) per long rest.

Professional Pride

You have become so practiced in your craft, it has become second nature to you. Starting at level 13, you gain proficiency in any checks which benefit from the advantage granted by your Finding The Flaw feature; if you already have proficiency in whichever skill is associated with the check, it is doubled for this check. Additionally, you add half your Intelligence modifier rounded up (minimum of one) when determining how many Alchemical Compounds you can create and carry per day.

Perfected Potency

At 17th level, you have mastered your alchemical prowess, refining your compounds for maximum effect. Your Alchemical Compounds deal an extra 1d10 of a damage type associated with them, and the amount of area they effect, or duration which they last, is doubled (your choice when activating the compound).