Whether they come from a standard source book or the darker corners of your imagination, the creatures your party faces can have a dramatic influence on the tone of your sessions and your players’ experience. The following functions are meant to help DMs either find creatures that meet their needs or homebrew new antagonists to face off against their players.
If you want to identify creatures defined by official D&D source
books, the creature_list function can be a helpful
mechanism for narrowing your search. This function lets you search
through official creatures based on criteria you specify. A dataframe
including all of the big-picture information for creatures that meet
your criteria is returned to help orient you for any subsequent steps
you plan on taking. Note that all creature_list arguments
that accept characters are case in-sensitive and queries use
partial string matching so you don’t need to try to engineer exact
matches.
See the help file for monster_list for the full list of
supported query criteria.
# Find all small creatures with 'goblin' in their name
gobbo_df <- dndR::creature_list(name = "goblin", size = "small")
# Check the structure of that output
str(gobbo_df)
#> 'data.frame': 7 obs. of 23 variables:
#> $ creature_name : chr "Dust Goblin" "Fire Goblin" "Goblin" "Goblin Boss" ...
#> $ creature_source : chr "Tome Of Beasts" "Tome Of Horrors" "Monster Manual" "Monster Manual" ...
#> $ STR : chr "8 (-1)" "14 (+2)" "8 (-1)" "10 (0)" ...
#> $ DEX : chr "16 (+3)" "18 (+4)" "14 (+2)" "14 (+2)" ...
#> $ CON : chr "14 (+2)" "13 (+1)" "10 (0)" "10 (0)" ...
#> $ INT : chr "10 (+0)" "16 (+3)" "10 (0)" "10 (0)" ...
#> $ WIS : chr "8 (-1)" "10 (+0)" "8 (-1)" "8 (-1)" ...
#> $ CHA : chr "8 (-1)" "12 (+1)" "8 (-1)" "10 (0)" ...
#> $ creature_size : chr "small" "small" "small" "small" ...
#> $ creature_type : chr "humanoid" "humanoid" "humanoid (goblinoid)" "humanoid (goblinoid)" ...
#> $ creature_alignment : chr "neutral evil" "neutral evil" "neutral evil" "neutral evil" ...
#> $ creature_xp : int 50 2900 50 200 100 1100 200
#> $ creature_cr : num 0.25 7 0.25 1 0.5 4 1
#> $ languages : chr "common, goblin" "common, goblin, sylvan" "common, goblin" "common, goblin" ...
#> $ skills : chr "Stealth +7" "Deception +4, Perception +3, Stealth +7" "Stealth +6" "Stealth +6" ...
#> $ speed : chr "40 ft." "20 ft." "30 ft." "30 ft." ...
#> $ hit_points : chr "5 (1d6 + 2)" "45 (10d6 + 10)" "7 (2d6)" "21 (6d6)" ...
#> $ armor_class : chr "14 (leather armor)" "15 (natural armor)" "15 (leather armor, shield)" "17 (chain shirt, shield)" ...
#> $ senses : chr "darkvision 60 ft., passive perception 9" "darkvision 120 ft., passive perception 13" "darkvision 60 ft." "darkvision 60 ft." ...
#> $ saving_throws : chr "" "DEX +7, CON +4" "" "" ...
#> $ damage_immunities : chr "" "fire" "" "" ...
#> $ damage_resistances : chr "" "lightning; bludgeoning, piercing, and slashing from nonmagical weapons" "" "" ...
#> $ condition_immunities: chr "charmed, frightened" "" "" "" ...If you need to access the specific description of a particular
creature (or creatures), you can use the creature_text
function. This returns an R-style dataframe equivalent of the sort of
creature card information you’d find in the back of a typical D&D
source book.
The DMG provides a table (see p. 274) that gives the vital statistics
of creatures based on their Challenge Rating (CR) but this table can be
cumbersome to compare to Experience Points (XP) which are the numbers
actually used to balance encounter difficulty. While there are functions
that go further, at its simplest it can be nice to convert CR into XP.
To that end, the cr_convert function can perform this
conversion without too much stress.
Now that we can do this conversion easily, we can use other
dndR functions to go further.
As referenced above, the DMG provides a nice table linking CR to
standard monster statistics. If you’d rather avoid using that table you
can instead use the monster_stats function to gather the
information for which you are looking. To use this function, input
either the XP you want to spend on this creature or the
Challenge Rating (CR) if you know it.
Once either XP or CR is provided, monster_stats returns
the creature’s statistics as they appear in the DMG for a
single creature of that difficulty.
# Find the statistics of a single creature worth 8,000 XP
dndR::monster_stats(xp = 8000)
#> # A tibble: 8 × 2
#> statistic values
#> <chr> <chr>
#> 1 Challenge 11
#> 2 DMG_XP 7200
#> 3 Prof_Bonus 4
#> 4 Armor_Class 17
#> 5 HP_Range 221-235
#> 6 HP_Average 228
#> 7 Attack_Bonus 8
#> 8 Save_DC 17Note that if both CR and XP are specified, XP is ignored in favor of CR. My assumption is that if you use CR you prefer it over XP.
If you’d rather lean more into homebrewing your own monsters, the
monster_creator function may be of interest. This function
follows the advice of Zee
Bashew on how to build interesting, challenging monsters for your
party. These monsters are built somewhat according to the Dungeon
Master’s Guide for creating monsters, partly Zee’s YouTube video on
homebrewing monsters based on the video game The Witcher,
and partly on my own intuition about scaling the difficulty of a
creature.
Creatures are spawned randomly so you may need to re-run the function several times (or mentally modify one or more parts of the output) to get a monster that fits your campaign and players. Each creature is provided with up to five damage resistances, up to two damage immunities, and a single damage vulnerability. This combination allows you to build complex and mysterious homebrew monsters with plenty of opportunities to reward player investigation and insight in discovering the monster’s strengths and weaknesses before the final showdown.
# Make a monster for a 4-person party of level 5
dndR::monster_creator(party_level = 5, party_size = 4)
#> statistic value
#> 1 Hit_Points 92
#> 2 Armor_Class 16
#> 3 Prof_Bonus 3
#> 4 Attack_Bonus 7
#> 5 Save_DC 16
#> 6 Prof_Saving_Throws CHA; INT
#> 7 Immune_to fire; thunder
#> 8 Resistant_to force; lightning; necrotic; piercing; poison
#> 9 Vulnerable_to bludgeoning
#> 10 STR +2
#> 11 DEX +1
#> 12 CON +1
#> 13 INT +1
#> 14 WIS +3
#> 15 CHA +1Note that if you use monster_creator you may need to
help your players identify the creature’s immunities and vulnerabilities
before the actual confrontation with the creature to avoid
sending them into a fight that is more difficult than your party can
handle.