Every number on this page is arithmetic you can check: Torchline budgets 1,000 XP per character at level 9 for a standard fight, scales it by party size, then by the difficulty band. Below each table are the SRD 5.1 creatures that actually land in that budget.
Budgets by party size and difficulty
Difficulty
Party of 3
Party of 4
Party of 5
Party of 6
Skirmish — resources barely dented
1,650
2,200
2,750
3,300
Standard — a real fight, rarely lethal
3,000
4,000
5,000
6,000
Hard — someone will probably go down
4,800
6,400
8,000
9,600
Brutal — a character can die here
7,200
9,600
12,000
14,400
These are effective-XP budgets: a group of monsters is multiplied up before it is compared against them, so a budget of 4,000 does not mean 4,000 XP of monsters.
What actually fits, for a party of four
The crowd multiplier is the part that catches people out. Two creatures count for 1.5× their XP, three to six count double, seven to ten count 2.5×, eleven or more count triple. So the XP you can spend per creature falls fast as the group grows.
Skirmish — budget 2,200
A lone threat — about 2,200 XP each (×1 crowd multiplier)
Creature
Type
Size
CR
AC
HP
XP
Chimera
Monstrosity
Large
6
14
114
2,300
Drider
Monstrosity
Large
6
19
123
2,300
Invisible Stalker
Elemental
Medium
6
14
104
2,300
Mage
Humanoid
Medium
6
12
40
2,300
Mammoth
Beast
Huge
6
13
126
2,300
A pair — about 733 XP each (×1.5 crowd multiplier)
Creature
Type
Size
CR
AC
HP
XP
Basilisk
Monstrosity
Medium
3
12
52
700
Bearded Devil
Fiend
Medium
3
13
52
700
Blue Dragon Wyrmling
Dragon
Medium
3
17
52
700
Doppelganger
Monstrosity
Medium
3
14
52
700
Giant Scorpion
Beast
Large
3
15
52
700
A group of four — about 275 XP each (×2 crowd multiplier)
Creature
Type
Size
CR
AC
HP
XP
Animated Armor
Construct
Medium
1
18
33
200
Brass Dragon Wyrmling
Dragon
Medium
1
16
16
200
Brown Bear
Beast
Large
1
11
34
200
Bugbear
Humanoid
Medium
1
16
27
200
Copper Dragon Wyrmling
Dragon
Medium
1
16
22
200
A swarm of eight — about 110 XP each (×2.5 crowd multiplier)