Drow are uniquely positioned in the story of Baldur’s Gate 3 to be exceptional infiltrators. Drow characters are often allowed free access to enemy camps — usually without even needing to pass persuasion or deception checks. A build that can best capitalize on these enemy oversights is none other than the infamous 
Assassin / 
Gloom Stalker.
In this guide, we’ll cover how to build your infiltrator from character creation, all the way up to max level. If you’re unfamiliar with the synergy between these two classes, no worries; we’ll explain how their class skills can mix to create lethal outcomes. Additionally, effective equipment and strategies will be reviewed to cover all the bases.
Summary
The Assassin / Gloom Stalker class combination has become well-known, and for good reason. A character that has invested a lot into dexterity can seamlessly multi-class between the two and benefit from a wide range of complimentary skills and class actions. These builds can devastate enemy ranks at the start of combat, but also be very impactful outside of combat with their abilities to pick locks and pockets.
Character Creation
As the name implies, choosing a 
Drow for the race is a crucial aspect of this build. If you haven’t played the story yet, then you’ll see early on how this race can easily be mistaken as friendly to enemies. They also automatically have access to weapon proficiencies that suit an assassin (short swords, rapiers, hand crossbows), and they have access to apt features and spells like 
Superior Dark Vision and Darkness.
Leaning all the way into this character’s abilities, we selected the 
Urchin background to gain those extra bonuses in 
Sleight of Hand and 
Stealth. When divvying up the stats, we actually leaned a little more into charisma than might be expected. This is a good pick (along with insight) because being a Drow doesn’t automatically gain you access everywhere, and to be an infiltrator you have to get through the door first.
Leveling Up
There is definitely some wiggle room for customization, especially with spells and towards the latter levels. For each level, we will explain the character’s new features and our reasoning for every choice. For some levels, there aren’t any choices to actually make, so the section is used to explain your new options, and/or discuss the utility of what you gain.
Sneak Attack (Melee and Ranged)
This class action comes with the rogue class. It can be used when the character has an advantage over the enemy, like when attacking from stealth, when the enemy is surprised, or when a companion is next to the enemy. Mastering this skill is essential to the build.
Skill Proficiencies
We decided that these skills (shown above) would be the best for an infilitrator. However, you could lean into a bit of 
Performance to maybe distract enemies, but we thought 
Insight was better for general conversational advantages.
Dancing Lights (Spell)
This spell is given to Drow characters at level 1. It isn’t the best for assassins, but it can help in a scrap if your companions are having a hard time seeing enemies.
Cunning Actions
At first, these might be confusing because you already have access to ‘Hide’, ‘Disengage’, and ‘Dash’ as regular actions. The difference is that these are used as Bonus Actions. Hide will be used the most often, and typically at the start of a turn, so the rogue can gain advantage and attack with a sneak attack.
Subclass
This is where you finally choose to be an Assassin and gain the class’s three deadly passives:
Assasinate: Initiative – You gain an advantage for attack rolls on enemies that haven’t taken their turn yet. Since we have a high dexterity, we will usually be attacking first (initiative) meaning this advantage is used frequently.
Assasinate: Ambush – This passive turns all successful attack rolls against surprised targets into critical hits. With this build, you will want to be starting the fight sequences to gain the surprised advantage.
Assassin’s Alacrity – Let’s say you sneak attack an enemy, thus starting combat. That original sneak attack action is replenished instantly, meaning you can attack again.
Sneak Attack Damage
Goes up from using 1D6 to using 2D6.
Multi-Class to Ranger
It is important to change over to Ranger as early as possible because you will be able to capitalize on the class combinations sooner. We will talk about these as they come up in following level-ups.
True Strike
Gain advantage on your next attack roll. This isn’t the most useful since assassins already gain advantage by having a high dexterity and attacking first in the round.
Find Familiar
This summoning spell brings an allied animal form of your choosing to your side. This is actually a great situational tool for assassins. If they’re caught in a fight where they can’t hide and no companions are around, they can put this animal form next to the enemy to gain advantage, allowing them to use sneak attacks.
Spells
- Fog Cloud
- This is a basic spell that can obscure the sight of enemies. An infiltrator can use this to block vision, so they can hide, which allows for sneak attacks.
- Hunter’s Mark
- This won’t do much good on normal enemies, as it’s almost always better for the infiltrator to perform a sneak attack for immediate damage. However, on bigger enemies, like bosses, where you can score 3-4 attacks on a single enemy, this is a good tool to boost your damage numbers.
Fighting Style
This is one of those decisions that really depends on party composition and play style. We found the most value in archery, as it is the easiest to perform sneak attacks with ranged weapons while staying out of danger. If your party is lacking some close quarter units, then perhaps going with defense or dueling is a better option.
Subclass
Gloom Stalker, now you can meld the two lethal classes together and gain a big bump in passive abilities from the 
Ranger subclass.
Features
Dread Ambusher: You gain +3 initiative, and, on the first round of combat, you are granted more movement distance and an attack that can do an additional 1d8 damage.- Superior Darkvision: You already get this with being a Drow, but if you chose a different race then this will definitely be a nice bonus to seeing enemies in dark venues.
Actions
- Dread Ambusher: Hide – Another redundant buff, since you already have the hide feature as a bonus action from the assassin subclass.
- Umbral Shroud – When you are obscured, you can use your main action to become invisible. This doesn’t take a long or short rest, and isn’t a spell, making it one of the best invisibility actions.
Spells
- Disguise Self – Perfect for an infiltrator, especially since we chose Drow and they have a reputation for being an enemy race. Note: this can also be used when trying to use the spell ‘speak with dead’. Sometimes the dead won’t talk with their killer, unless they’re disguised.
Choose Spell
You have some freedom here as there are a couple of options suitable for the build, but we found one that we liked most.
- Hail of Thorns – This is a decent offensive spell on its own merits, but we chose it as an infiltrator for one specific reason. After sneak attacking, you will sometimes leave an enemy very close to dying, and that’s when this spell will come in handy. It can be used with a bonus action, and even when they make a saving throw, it still does half explosive damage.
Feat
There are quite a few options, but the Alert feat is the best. It raises the character’s initiative by 5, which makes it almost always go first in the turn order. Due to the advantages of Assassinate: Initiative, this is an easy choice.
Features
- Extra Attack: This is where things get fun! Now you can attack two times in one turn. That means that on opening turns of combat, you can really dish out some damage. However, you have to be creative with ways to gain advantage if your enemies aren’t surprised, so you can sneak attack them.
- Gain 2 Spell Slots (Level 1 and 2)
- We chose the level 2 spell, Pass without a Trace. This spell helps the whole party pass stealth checks. It’s very helpful when you need to bring another companion with you on your stealth escapades.
- Misty Step (Level 2 Spell) – A great spell for battles where you start at a disadvantage. Can be used to teleport to higher ground (preferably out of enemy sight), where the infiltrator will have a ranged attack advantage.
There are a lot of options from here on out. You can stick with the leveling up the Gloom Stalker to gain features against certain enemies and more skills, or you can switch back to the Assassin, which will help more with survivability and damage output. We opted for the Assassin, but if you are on an easier difficulty, you might want those ranger abilities.
Rogue Class Change
Feat
There are two feats that we would recommend depending on play style and where you feel it’s more needed: 
Mobile – which increases movement distance, so the infiltrator can more easily arrive at hiding spots or enemies, or 
Ability Improvement – crank up the dexterity with two extra skill points to ameliorate the damage with ranged and finesse weapons.
Features
Uncanny Dodge – You now only take half the damage from normal attacks. This will help a lot if you fail a check or are caught behind enemy lines.- Sneak Attack Improvement – Sneak Attack now does 3d6 damage.
Add Expertise to Two Skills
- Stealth – It might be a little overkill, but stealth is really what makes this build tick, so lean into it.
Perception – Give your perception a boost, so you can find secrets and traps easier while infiltrating.
Features
- Evasion – This passive allows your character to take no damage from spells when they roll a successful dexterity saving throw (even from spells that normally do half damage on a saving throw).
- Sneak Attack Improvement – Sneak attack now does 4d6 damage.
Equipment
Most of the equipment that we will recommend in Act 1 is in the Underdark. There are several ways to get to the Underdark, but we don’t recommend rushing there, as enemies are quite difficult if you’re underleveled.
Act 1
- Shortsword of First Blood
- Can be found on a dead gnome east of the fast travel point for the Underdark. (X:72 Y: -183)
- If it isn’t there, it will be on a dead Duergar that’s also east of the Underdark fast travel point and up a cliff. (X: 30 Y: -161)
- This shortsword adds 1d8 piercing damage to target’s with full health. Perfect for assassin’s that want to buff their damage ouput.
- Phalar Aluve (Longsword)
- Found in the Underdark, it is a sword that is stuck in a stone just outside of Selunite Fort. (X:119 Y:-191)
- It is unique because it is a longsword that scales with Dexterity (because it has the ‘finesse’ modifier). It also has an interesting special action to buff allies, or debuff enemies.
- Spidersilk Armor
- Can be found on Minthara. She will be in the northeast corner of the Shattered Sanctum in the Goblin camp (X:-551, Y:231), but she will move depending on story choices.
- This light armor gives a +1 to stealth checks and gives a bonus to constitution saving throws. Exactly what an infiltrator needs to stay alive and hidden.
- Shadow of Menzoberranzan (Head Armor)
- It can be found after finishing the quest ‘Protecting the Myconid’, which is started by talking to the Myconid Sovereign in the Myconid Camp in the Underdark. After the quest, the Sovereign will allow access to a part of the colony that has a dead Drow inside. Next to the Drow is the helmet. (X:55, Y:-68). This area’s door (vines, really) can be opened by other means, but at the risk of the colony attacking you.
- This head piece allows the wearer to use ‘Shrouded in Shadow’, allowing them to be invisible for 2 turns. An excellent tool to have in the early game, and only requires a short rest to replenish the action.
- Disintegrating Night Walkers
- Can be looted off of True Soul Nere’s Body in Grymforge. (X:-637, Y:309)
- Gives the ability ‘Misty Step’, allowing for teleportation once per short rest. There are countless ways an infiltrator can make use of these: warping to higher ground, past guards, or into sneak attack distance are just a few examples.
- Gloves of Power
- Can be found by looting some of the goblins that attack the Emerald Cove. (X:207, Y:437)
- If you receive the Brand of the Absolute from Priestess Gut, these make an enemy attacked by the wearer have a penalty on their future attack and saving rolls.
- For our build, though, these give the wearer +1 to Sleight of Hand, which helps you with pickpocketing!
Strategy and Tactics
The infiltrating part of this build is pretty easy, because most of the time you can just pretend to be an ally of the goblins and the Absolute. Sometimes, you will need to use some sort of skill check while in dialogue to keep up appearances. For this reason, it is a good idea to keep Shadowheart in your party, so you have access to the cantrip, 
Guidance. This helps with all ability checks, and there’s no limit to how much it can be used.
The real nuances of using this build come about in combat, and even more often, just before its initiation. All the passive perks and features of this build are front loaded to be advantageous when you start combat and on the first round. For this reason, you want to always be initiating combat, and not giving your enemies a chance to attack first.
Practice positioning your infiltrator where they can use their hide ability and start combat with a sneak attack on a more dangerous enemy. If you can do that effectively, you’ll find that you regularly have an entire free round of attacks with your party while the enemies are surprised. While they’re surprised, you can also use sneak attacks without being hidden. That means that your bonus action is free to use for more movement, or to use offensive spells, like Hail of Thorns.
For the rest of combat, you will want to be using the infiltrator’s turn to find a place to hide (where enemies can’t see you), and from there, use a sneak attack on an enemy. You can hold 
to see enemies’ lines of sight (when you’re not sneaking). When you can’t use your hide bonus action for a sneak attack, go and attack an enemy that is close by an ally. If a companion is close to an enemy, you still receive an advantage to use a sneak attack on that enemy. As you level up (see leveling above), you’ll receive more passives and bonuses, but the main technique remains the same.
