Here's some NPCs to throw at the players, based on some M:TG cards, great way to introduce some demonic cults that can be reoccurring villains or villain of the week.
Acolyte of Xathrid
The Acolyte serves the Cult of Xathrid, a group of demons, humans and gorgons dedicated to the major demon Xathrid on the plane of Shandalar. They are low level clerics that serve the cult by offering blessings only to those deemed worthy. They preform various lower level rituals, such as minor sacrifices, recruiting, supporting low level members in various cult
Acolyte of Xathrid
Type: Humanoid (typically human)
Size: medium
CR: 2
Hit Points: 16
Mas: 12
Init: +1
Speed: 30 ft
Defense: 14 (+1 Dex, +3 Class +1 armour), Touch 14, flat-footed 13
BAB/Grp: +2/+2
FS/Reach: 5 ft
Attacks: +2 melee ritual dagger (1d4 piercing), or +3 ranged 9mm pistole (2d6, 30 ft, ballistic, 8 box)
Special Attacks: Essence Drain
Special Qualities: Shadow Initiate
Allegiances: Xathrid
Saves: Fort +3, Reflex +2, Will +5
Reputation: +1
Abilities: Str 10, Dex 12 (+1), Con 12 (+1), Int 15 (+2), Wis 13 (+1), Cha 12
Skills: Bluff +2, Diplomacy +2, Concentration +7, Intimidate +2, Knowledge (Arcane Lore) +10, Knowledge (Current Events) +4, Listen +5, Sense Motive +7, Spot +5
Feats: Empathy, Skill Emphasis (knowledge arcane lore), simple weapon proficiency, personal weapon proficiency, Iron Will, Mana Manipulation, Convert Mana
Possessions: Ritual dagger, Colt 9mm pistol with 3 magazines, concealed vest, cell phone (with encrypted occult apps for ritual timing and rites), dark raiment (+2 to Hide checks in dim lighting)
Mana: 15 Mana total (8 raw, 7 Black Mana), mana attack (1 mana, 1d4 energy, 50 ft), mana shield (5 mana, 10 hp, 1 minute)
Combat Tactics
The Acolyte is a harasser not a front-line tank, preferring to stay behind cover of tougher allies and will use the Essence Drain ability for targets within range to wound enemies and heal themselves, otherwise use their pistol or mana attack if there's planet of mana in the area. For potent foes they will use their mana to enhance their Essence Drain ability. Worthy foes, when weakened, they will close the gap and use their dagger to deliver sacrificial blow, releasing more mana.
Shadow Initiate
Members of the Cult of Xathrid are trained in the use of mana manipulation, as well as allows access to exclusive abilities, depending on their role. If the Acolyte uses their ritual dagger to deliver the killing blow to a living creature (minimum of 1 point of damage), the creature they kill releases mana equal to double their Constitution, which the Acolyte can absorb half to their mana pool, the other half is sent to Xathrid, who uses it to fuel their dark plans. If the creature killed has a mana pool, all of the creature's remaining mana is channeled to Xathrid, although the Acolyte can, with a Concentration check DC 20, can absorb half the mana pool, in addition to the half from the mana from the creature's doubled Constitution score.
Essence Drain (Su)
Acolytes, clerics and priests of the Cult of Xathrid are trained how to drain the essence of other living beings through mana manipulation. As a standard action, the Acolyte may target a single living creature within 30 feet as a ranged touch attack (+3 ranged), which must make a Fort save DC 13. If they fail, they suffer 1d4 necrotic damage, and the Acolyte gains the same amount of hit points, up to their maximum. Usable every 1d4 rounds (roll once at start of combat). May channel 2 points of mana to either increase the Fort save DC by +1, or increase the damage by +1, to a maximum of +5. If using Black Mana, 1 black mana to increase the Fort save, or 2 Black Mana to increase the damage by +1d4, to a maximum of +5 to DC, or 4d4 damage.
Feat: Mana Manipulation (General, Mana)
Prerequisites: Intelligence 4+
Benefits: The user can use raw magical energy, or mana, for use in some basic magical abilities, or can use it to power their class magical powers. Alternatively, they can use their class magical abilities and convert them to mana.
A person has mana point pool that is equal to their Intelligence, and requires a minimum of 4 Intelligence, and is able to manipulate mana in a few basic ways. A character with a class with spell slots can use their mana to power their magic, using mana to equal the spell slot level to power a spell. For example, a level 3 spell requires three mana points to power, while a single mana point is required to power a level 1 or level 0 spell. A user can recover mana at a rate of 1 per hour of rest +1 per Wisdom Modifier (negative modifier does not reduce recover, just doesn't increase, functions as +0). The user can also use mana to provide the spell slots for when using metamagic feats, such as empower spell, etc.
Alternatively they can use a spell slot to create mana, with the spell slot level equaling mana points, thus a level 3 spell slot converts into 3 mana points.
The user can use this mana in several basic ways, attack, heal, or defense, improve natural ability.
For attack, the user can use mana to fire an energy ball from their palm, using 1 mana point to deal 1d4 points of energy (counts as magical) damage plus Int modifier (a negative Intelligence modifier doesn't lower damage, doesn't add any though), with a range of 30 feet plus 10 feet / Int modifier, as a ranged touch attack.
For healing, the user can use mana to recover hit points in a creature touched or themselves, using 2 mana points per 1 hit point recovered. Thus if they used 10 mana points, they can heal 5 hit points.
For defense, they can create a bubble shield around him/herself for 5 mana points that can function for 1 minute, able to absorb 10 points of damage. Each additional point of mana used increases the amount of damage absorbed by 2, and each 5 points used (while increasing damage absorbed), increases duration for 1 minute.
For Improve natural ability, the user can spend 5 mana points to improve 1 ability score by +2 for 3 rounds (Strength, Dexterity, Constitution, Intelligence, Wisdom and Charisma), or improve one type of their movement by 20 feet for 3 rounds, or any one other racial extraordinary ability (such as darkvision, breath weapon, tremorsense, etc) by 25% for fixed numbers, or 1 extra die if variable number, or duration by 25%, rounding down, for 3 rounds
Convert Mana (General, Mana)
You can change your stored mana, or mana you absorb from the environment into specific types of mana.
Prerequisite: Int 15, Con 12, Wis 12, Mana Manipulation, Mana Battery
Benefit: You can change some mana in your mana pool, or the mana in the environment you absorbing into a different type at a rate of 2 mana to convert to 1 mana of the new type, taking a move equivalent action and a Concentration check DC 15, converting a maximum of Int modifier plus Wis modifier mana, however for every 5 points over the DC, can convert an additional 1 mana. For example, can convert 6 mana in mana pool, which is basic raw type into 3 of any particular type such as white or red, but all converted must be the same type. Mana converted within the user's mana pool is stored as that type of mana until used, while mana absorbed from the environment must be used within 3 rounds, unless it is being used to replenish already depleted mana pool until reaching normal max mana.
Xathrid Cruel Sadist
The Xathrid Cruel Sadists are loyal fanatics of Xathrid that function as enforcers, bruisers and heavy hitters, inflicting injuries on themselves for increased temporary power. They will guard acolytes and bring new sacrifices to them.
Xathrid Cruel Sadist
Type: humanoid (typically human)
Size: Medium
CR: 3
Hit Points: 31
Mas: 14
Init: +2
Speed: 30 ft
Defense: 16 (+2 Dex, +2 Class +2 Leather Jacket), touch 14, flat-footed 14
BAB/Grp: +2 / +4
FS/Reach: 5 ft x 5 ft / 5 ft
Attacks: +4 melee barbed spiked gauntlet (1d6+2) or +4 ranged sawed-ff shotgun (2d8, ballistics, 10 ft)
Special Attacks:
Special Qualities: Self-Harm Ritual, Release the Agony, Robust
Allegiances: Xathrid
Saves: Fort +5, Reflex +3, Will +2
Reputation: +1
Abilities: Str 14 (+2), Dex 15 (+2), Con 14 (+2), Int 10, Wis 12 (+1), Cha 8 (-1)
Skills: Concentrate +6, Intimidate +5, Spot +3, Survival +4, Treat Injury +3
Feats: Simple weapons proficiency, simple weapons proficiency, power attack
Possessions: leather jacket, pain killers, barbed spike gauntlet (+2 to avoid being disarmed), sawed-off shotgun, 20 rounds.
Combat
When combat is expected, will typically spend first round behind cover to use Self-Harm Ritual to buff herself, then charges into combat, leading with the shotgun before engaging in melee. Once a target is wounded, will use Release the Agony to deal damage directly to them, typically either the weakest foe as a show of force, or the strongest to allow accompanying acolytes to preform a killing blow. The Sadist will use additional uses of Self Harm Ritual between foes to increase the damage before engaging a particularly powerful foe, or to build up the fear before engaging the weakest.
Self-Harm Ritual (Ex)
As a move action, the Sadist can intentionally cut herself to, dealing 1 point of Constitution damage. In exchange, gains a demonic bonus of +1 to attack and damage rolls and DR 1 for the next minute. Can stack up to 5 times.
Release the Agony (Su)
As a standard action, the Sadist can spend the built-up pain (stacks of Self-Harm Ritual), selecting a target they can see within 10 feet, making a ranged touch attack at +4, dealing 1d6 nonspecific energy per stack of Self-Harm Ritual, the target his hit with waves of psychic agony, screaming in pain. If the damage is greater than the target's Constitution, must make a Will save DC damage dealt or be paralyzed in pain for 1 round.
Robust
The Sadist recovers ability damage at double normal speed (2 points per rest instead of normal 1). The Sadist also ignores subdual damage.
Cult Conscript
The Conscript is a "Disposable Asset"—a reanimated urban soldier, perhaps a fallen gang member or a corporate security guard brought back via a "Necro-Link" server or dark rituals. He’s cheap, aggressive, and incredibly annoying to keep down. There is a tattoo or brand that glows and humbs when the Xathrid Reanimation is triggered.
Cult Conscript
Type: Undead Humanoid (typically human)
Size: Medium
CR: 1
Hit Points: 13
Mas: -
Init: +1
Speed: 30 ft
Defense: 15 (+1 Dex, +2 Class, +2 Uncovered Vest), touch 13, flat-footed 14
BAB/Grp: +1 / +2
FS/Reach: 5 ft by 5 ft / 5 ft
Attacks: +2 melee spiked club (1d6+1), or ranged Glock 17 (2d6, ballistic, 30 ft, 17 box)
Special Attacks:
Special Qualities: undead traits, Xathrid Reanimation
Allegiances: Xathrid
Saves: Fort +3, Reflex +1, Will +1
Reputation: 0
Abilities: Str 13 (+1), Dex 12 (+1), Con -, Int 8 (-1), Wis 10, Cha 8 (-1)
Skills: Climb +3, Jump +3, Hide +3, Move Silently +3
Feats:
Possessions: Undercover vest, tattered clothing (typically bloodstained), Glock 17, 3 magazines, spiked club
Combat
The Constrict charges into combat, firing their pistols until they close to melee combat, unless ordered to remain close to specific person or spot, then engage in melee with their clubs. They will protect Acolytes and Cruel Sadists whenever possible. When paired with a Cruel Sadist, when they use their Self-Harm Ritual, the bleeding from the ritual satisfies the requirement for the Conscript to reanimate, allowing it to continue combat.
Xathrid Reanimation
The Cult Conscript is capable of reanimating after being reduced to 0 HP if a living creature (ally or enemy) has been reduced to 0 HP or killed within 30 ft of where the Conscript was destroyed during the current or previous round. The Conscript takes 1 full action to knit back together after the living being is reduced to 0 HP, absorbing it's life force, standing up with half its maximum HP (6 HP). This ability can't be used if the Conscript was destroyed by holy water, fire, or a weapon with the Blessed or Holy properties.
If a Cruel Sadist uses their Self-Harm Ritual within 10 feet of a destroyed Cult Conscript, up to 3 rounds after its destruction, the Conscript will reanimate as normal, instead of being done the same round or round after.
If an Acolyte uses their ritual dagger to reduce a living being to 0 HP within 50 feet of a destroyed Cult Conscript, within up to 3 rounds after its destruction, the Conscript will reanimate, at maximum hit points and gain a +1 to attack rolls and damage for 3 rounds after it is up, but the Acolyte doesn’t gain any mana from the being's death. The Acolyte can trigger the Reanimate with full hit points and bonus to attack and damage for up to 5 Conscripts with a single kill with the ritual dagger.