ABERRATION GENERATION!!! (5e)

From an early draft of Teratogenicon:

Aberrations are utterly alien beings. Many of them have innate magical abilities drawn from the creature’s alien mind rather than the mystical forces of the world. [from the SRD]

Aberrations are the strangest and most variable type of monster. A giant with two heads or blue skin is still a giant; a giant with a head on its stomach, a serpent for a tongue and half a dozen slimy tentacles where the legs should be is probably an aberration.

Some aberrations are very intelligent while others are dumber than farm animals, but most of them are utterly unpredictable. Their alien, deranged minds are capable of feats unknown to most of humankind – innate magic, telepathy, baffling schemes and calculations – but can also make them erratic and self-destructive. Few aberrations have humanlike capacities – most are either incredibly gifted or incredibly stupid, although some appear to be both.

Habits, diet and habitat

Aberrations are alien enough to defy comprehension. They are mostly inscrutable, although many behave like common predators, killing for food and sport. Most aberrations need food and water to survive, although some seem to subside on psychic energies, ether, or other mystical energies. They often live in forgotten dungeons, temples and caves, away from human eyes, since none in their right mind would suffer them to exist.

Traits

A typical aberration has the following traits:

Size: any.

Alignment: Chaotic Evil.

Abilities: good Strength, Constitution; bad Charisma, Intelligence.

Senses: darkvision 60 ft.

Languages: Few aberrations can comprehend languages and even fewer can speak. If they do, it is likely Deep Speech, Common, or Undercommon.

Challenge: 2d6.

Attacks: upper limbs (see below) and others.

Appearance. The first five tables describe an aberration’s appearance – skin, upper and lower limbs, body and special features. There is no entry for heads – the head, if any, will be appropriate to the body most of the times (amoebas will rarely have heads, octopuses have heads and no bodies, etc.). However, you can roll twice on the body table to produce a different head.

A monster with no upper limbs must attack with the lower limbs or other body parts (bite, slam, etc.). A monster with no lower limbs may use pseudopods, some form levitation, move with the upper limbs, or just roll around.

  

Special Powers

1. Genius: The monster has genius-level Intelligence (18 or more), knows a few languages and mental skills, and gains one additional special attack appropriate for an intelligent creature (psionic blast, ray gun, spellcasting, etc.).

2. Telepathy: The monster can magically transmit simple messages and images to any creature within 120 feet of it that can understand a language, and detect the overall intentions of their foes from the same distance.

3. False Appearance: While the monster remains motionless, it is indistinguishable from a common object, animal or terrain feature (rug, tree, cow, humanoid in robes, stalagmite, bundle of ropes, etc.).

4. Teleporting: As an action, the monster can teleport, along with any equipment it is wearing or carrying, up to 120 feet to an unoccupied space it can see.

5. Aberrant Ground: The ground in a 10-foot radius around the monster is difficult terrain (doughlike, frozen, slippery, filled with tentacles, etc.). Each creature that starts its turn in that area must succeed on a Strength saving throw or have its speed reduced to 0 until the start of its next turn.

6. Regeneration: The monster regains (2xCR) hit points at the start of its turn. If the monster takes one specific kind of damage (choose one from fire, acid, radiant, etc.), this trait doesn’t function at the start of the monster’s next turn. The monster dies only if it starts its turn with 0 hit points and doesn’t regenerate.

7. Carapace: the monster has a thick carapace that adds +2 bonus to AC and all Dexterity saving throws.

8. Fog: the monster is constantly surrounded by a thick fog (or illusion, cloud of darkness, etc.) that makes it invisible to all creatures that are not within 15 feet of the monster.

9. Four-dimensional: the monster lives in four dimensions and occasionally shifts out of existence. As a bonus action, the monster can roll 1d4. On a 1 or 2, nothing happens. On a 3, it shifts partially out of the three known dimensions, becoming heavily obscured. On 4, it enters a fourth dimension, where it is still visible yet it cannot affect or be affected by anything on the material plane. The effects last until the beginning of its next turn.

10. Shapechanger: The monster can use its action to polymorph into a Small or Medium humanoid it has eaten in the past, or back into its true form. Its statistics, other than its size, are the same in each form. Any equipment it is wearing or carrying isn’t transformed. It reverts to its true form if it dies.

11. Engulf: As an action, the monster engulfs a Medium or smaller creature Grappled by it. The engulfed target is Blinded, Restrained, and unable to breathe, and it must succeed on a Constitution saving throw at the start of each of the monster’s turns or take (2xCR) bludgeoning damage. If the monster moves, the engulfed target moves with it. The monster can have only one creature engulfed at a time.

12. Drain: As an action, the monster deals (CRx1) damage to a creature, and regains hit points equal to the damage the creature takes. The target must be grappled (blood drain) or charmed (psychic drain) by the monster.

13. Alien Mind: The monster is immune to scrying and to any effect that would sense its emotions, read its thoughts, or detect its location. In addition, if a creature attempts to do any of these things it must succeed on a Wisdom saving throw or take (CRx1) psychic damage and suffer the Stunned condition for one round.

14. Replicating: The monster is usually accompanied by 2d4 smaller versions of it, with lower CRs. The sum of their CRs cannot exceed the monster’s CR.

15. Horrific Appearance: Any humanoid that starts its turn within 30 feet of the monster and can see it must make a Wisdom saving throw. On a failed save, the creature is Frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, with disadvantage if the monster is within line of sight, ending the effect on itself on a success. If a creature’s saving throw is successful or the effect ends for it, the creature is immune to the monster’s Horrific Appearance for the next 24 hours. Unless the target is surprised, the target can avert its eyes and avoid making the initial saving throw. Until the start of its next turn, a creature that averts its eyes has disadvantage on attack rolls against the monster.

16. Magic Resistance: The monster has advantage on saving throws against spells and other magical effects.

17. Flying: The monster has a 30 feet flying speed.

18. Gibbering: The monster babbles incoherently while it can see any creature and isn't Incapacitated. Each creature that starts its turn within 20 feet of the monster and can hear the gibbering must succeed on a Wisdom saving throw. On a failure, the creature can't take reactions until the start of its next turn and rolls a d8 to determine what it does during its turn. On a 1 to 4, the creature does nothing. On a 5 or 6, the creature takes no action or Bonus Action and uses all its Movement to move in a randomly determined direction. On a 7 or 8, the creature makes a melee Attack against a randomly determined creature within its reach or does nothing if it can't make such an Attack.

19. Telekinetic field: While the monster is conscious, it has advantage in Strength and Dexterity saving throws. Melee attacks against the monster have disadvantage, and ranged attacks miss automatically.

20. Roll twice

Color images:  copyright WotC. B&W images: art by Rick Troula - see below!

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If you enjoyed this post, you'll certainly enjoy the final version: Teratogenicon, the ultimate monster builder! It is full of random tables like the ones above and it has amazing art by Rick Troula. Chek the previews to see what I mean!

Detailed initiative (5e) - Half turns, etc.

I've discussed 5e initiative here. As mentioned in the comments (thanks Sean and everybody that commented for the feedback), I like the idea of detailed initiative. The hard part is making it simple.

The idea:

Every fight begins with a fast turn. After this turn, everybody takes a slow turn, and so on.

In a fast turn, you can move half your speed (round down), make half you attacks (round down), etc.

In a slow turn, you can do the same, but round up. Most actions happen in the slow turn, but, like attacks, they are subjected to "halving" if possible (if you choose to "Dash", for example, you just double your movement for both turns).

It is very likely that you have to declare your action during or after the fast turn.

Let us say a fighter has three attacks and moves 35 feet in a turn: he could move 15 feet and attack once in a fast turn, and move 20 feet and attack twice in a slow turn.

Explanation:

As I've said,the problem is not easy to solve - but easy enough to reduce by half.

For example, instead of of having a whole turn where you get up, move 15 feet, and attack you opponent three times while he DOES NOTHING, a more "organic" solution would be something like: you move 10 feet, he moves 5 feet, you attack twice, he attacks once, you attack once more, then he attacks, etc.

The inspiration for this idea is Shadow of the Demon Lord, BTW.

Weapon speed

Two guys are facing each other, 30 feet apart. One has a dagger, the other a halberd. Who hits first? Obviously, the halberd (unless you THROW the dagger, which is an interesting distinction); but most RPGs that get to this level of detail say that the dagger attacks first (this includes the 5e DMG optional rules).

Which is why I'd say weapon speed shouldn't be about who attacks FIRST, but who attacks AGAIN first. The guy with the halberd might hit first, but the guy with a dagger could stab a foe three times during one halberd swing.

Easiest way to do this: a critical hit gives you a CHANCE to attack again. The faster the weapon (an the greater the number of attack you have), the greater the chance. Or, to make things faster, the GM could roll a single dice every round: every weapon with a speed above that threshold gains an extra attack.

If you want to account for weapon reach, being approached by a foe with a shorter weapon allows you to attack first if you're not engaged with anyone else (an opportunity attack would be an appropriate alternative to this).

Spells and spell interruption

I like the idea of spell interruption, which is not an important thing in D&D 5e. In this system, you could probably choose a spell to use in your fast turn, and only "fire" it in a slow turn. Alternatively, you could only use spells of a (spell slot) level that is half your maximum in your fast turns. For example, if you can cast 9th level spells, you could cast a 4th level spell in your fast turn, OR prepare a 9th level spell to cast in your slow turn.

I'm tempted to say that, in the first case, you could ALSO cast ANOTHER 4th level spell in your slow turn - provided you didn't lose concentration between turns.

Bonus actions/reactions/object interactions

I would probably allow reaction in BOTH rounds. Seems to me that it would be a welcome addition. Same goes for object interactions.

Bonus actions are trickier; limiting to one per round seems more reasonable, but see below.

Choices

One way to make this system more tactical is allowing some choice. Usually, you can move AND attack, but if you decide not to move, maybe you can take an additional bonus action (not more than one bonus action per turn), cast an additional spell (4th+4th, as seem below), or make an attack in your fast turn, if you have a single attack. If you have multiple attacks, you could use a crossbow multiple times without moving, or a net and trident, etc.

Pros

- Shorter turns means players pay more attention.
- The "ready" action makes a bit more sense.
- Tactical choices.
- Organic movement./attacks.
- Spell interruption.
- Interesting use for low-level spells at high levels.
- Action Surge looks better.
- TWF could be "fixed" by something like this (more object interactions, more bonus actions, etc). Same goes for crossbow, net, etc.
- More straightforward than checking the DMG table.

Cons

Frankly, this level of detail isn't appreciated by many, and I'm not sure I'm willing to put up with it. "old school" initiative, with phases and all, still sound a bit simpler to me. Still, for a combat-oriented game, I feel this could be fun.

Super-fast 5e monsters

If you know proficiency bonus, everything else is easy to find.

Attack bonus: proficiency x 2

Save DC: 8 + proficiency x 2

Damage: 5+(CRx5)

HP: 15+(CRx15)

"Good" saves/skills/checks: proficiency x 1.5

"Weak" saves/skills/checks: half proficiency, if any

AC: 10 + "Good" save.

Why? Well...

Attack bonus: double proficiency is meant to encompass both proficiency bonus an ability bonuses. These will be close to PC's bonuses.

Save DC: calculated like PC's save DCs.

HP and Damage: based on the DMG. Number of attacks is not that important. A limited attack ("recharge 4-6", etc.) affects a whole area (example: breath weapon) and, unless you succeed on a save, deal double damage (10+CRx10).

Good/weak saves: these are simplifications; monsters could have six different saves, but it is a decent approximation.

AC: start with unarmored. Since you don't add proficiency to AC most of the time, it is a bit lower than attack bonus. At high levels, monster will be easier to hit, but will be able to take more punishment as PC damage will not usually keep up with monster HP (at least for fighters).

Smoother table:

CR	Prof	x0.5	x1.5	x2
1	2	1	2	3
2	2	1	3	4
3	2	1	3	4
4	2	1	3	5
5	3	1	4	5
6	3	1	4	6
7	3	2	5	6
8	3	2	5	7
9	4	2	5	7
10	4	2	6	8
11	4	2	6	8
12	4	2	6	9
13	5	2	7	9
14	5	2	7	10
15	5	3	8	10
16	5	3	8	11
17	6	3	8	11
18	6	3	9	12
19	6	3	9	12
20	6	3	9	13
21	7	3	10	13
22	7	3	10	14
23	7	4	11	14
24	7	4	11	15
25	8	4	11	15
26	8	4	12	16
27	8	4	12	16
28	8	4	12	17
29	9	4	13	17
30	9	4	13	18

Special thanks: 

- Unknown user that commented here.

- Blog of holding.

UPDATE: If you want to create your own monsters, take a look at  Teratogenicon, our most impressive book so far. Check the previews to see for yourself!