The Hardest Binding of Isaac Bosses - Hardest Rankings

103 Enemies

473 Votes

10 Voters

Updated August 27, 2025

A list of all bosses from The Binding of Isaac: Rebirth, ranked from hardest to easiest.

We combined votes from 10 players to create this list.

Based on the latest version of The Binding of Isaac: Repentance.

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All 103 Binding of Isaac Bosses Ranked, Hardest to Easiest | Unduel

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1.Mega Satan
1.Mega Satan
Chapter 6
Final Boss
Boss
7
100
Rating
1.1
Spread
7
100
Rating
1.1
Spread

2.The Visage
2.The Visage
Chapter 3.5
Boss
5
100
Rating
1.6
Spread
5
100
Rating
1.6
Spread

3.The Scourge
3.The Scourge
Boss
Corpse
3
95
Rating
2.3
Spread
3
95
Rating
2.3
Spread

4.Ultra Greedier
4.Ultra Greedier
Final Boss
Greed Mode
Boss
6
93
Rating
3.7
Spread
6
93
Rating
3.7
Spread

5.Bumbino
5.Bumbino
Chapter 2
Boss
4
91
Rating
2
Spread
4
91
Rating
2
Spread

6.Ultra Pestilence
6.Ultra Pestilence
Boss
Home
4
87
Rating
7.2
Spread
4
87
Rating
7.2
Spread

7.The Heretic
7.The Heretic
Chapter 3.5
Boss
5
87
Rating
2.4
Spread
5
87
Rating
2.4
Spread

8.Delirium
8.Delirium
Final Boss
Boss
The Void
6
87
Rating
5
Spread
6
87
Rating
5
Spread

9.Daddy Long Legs
9.Daddy Long Legs
Chapter 4
Boss
4
83
Rating
6.9
Spread
4
83
Rating
6.9
Spread

10.Ultra Greed
10.Ultra Greed
Final Boss
Greed Mode
Boss
6
82
Rating
3.2
Spread
6
82
Rating
3.2
Spread

11.Mother
11.Mother
Final Boss
Boss
Corpse
6
81
Rating
5
Spread
6
81
Rating
5
Spread

12.Chimera
12.Chimera
Boss
Corpse
4
80
Rating
6.3
Spread
4
80
Rating
6.3
Spread

13.Hush
13.Hush
Final Boss
Boss
???
6
79
Rating
5
Spread
6
79
Rating
5
Spread

14.The Pile
14.The Pile
Chapter 2.5
Boss
5
79
Rating
5.7
Spread
5
79
Rating
5.7
Spread

15.Wormwood
15.Wormwood
Chapter 1.5
Boss
4
77
Rating
4.7
Spread
4
77
Rating
4.7
Spread

16.Ultra War
16.Ultra War
Boss
Home
4
76
Rating
9.6
Spread
4
76
Rating
9.6
Spread

17.Gurdy Jr.
17.Gurdy Jr.
Chapter 2
Boss
4
75
Rating
5.8
Spread
4
75
Rating
5.8
Spread

18.Dogma
18.Dogma
Final Boss
Boss
Home
6
75
Rating
4.6
Spread
6
75
Rating
4.6
Spread

19.Min-Min
19.Min-Min
Chapter 1.5
Boss
4
74
Rating
9.3
Spread
4
74
Rating
9.3
Spread

20.The Adversary
20.The Adversary
Chapter 3
Boss
4
72
Rating
4.9
Spread
4
72
Rating
4.9
Spread

21.Ultra Death
21.Ultra Death
Boss
Home
4
70
Rating
7.8
Spread
4
70
Rating
7.8
Spread

22.Mask of Infamy
22.Mask of Infamy
Chapter 3
Boss
4
68
Rating
4
Spread
4
68
Rating
4
Spread

23.Rag Man
23.Rag Man
Chapter 1
Boss
5
67
Rating
9.9
Spread
5
67
Rating
9.9
Spread

24.The Cage
24.The Cage
Chapter 3
Boss
4
66
Rating
10.9
Spread
4
66
Rating
10.9
Spread

25.Triachnid
25.Triachnid
Chapter 4
Boss
4
64
Rating
3.5
Spread
4
64
Rating
3.5
Spread

26.Mama Gurdy
26.Mama Gurdy
Chapter 4
Boss
4
64
Rating
6.6
Spread
4
64
Rating
6.6
Spread

27.Ultra Famine
27.Ultra Famine
Boss
Home
4
63
Rating
8.9
Spread
4
63
Rating
8.9
Spread

28.Blighted Ovum
28.Blighted Ovum
Chapter 1
Boss
5
62
Rating
6.6
Spread
5
62
Rating
6.6
Spread

29.Clutch
29.Clutch
Chapter 2.5
Boss
5
62
Rating
10.2
Spread
5
62
Rating
10.2
Spread

30.Steven
30.Steven
Chapter 1
Boss
5
62
Rating
9.5
Spread
5
62
Rating
9.5
Spread

31.Turdlings
31.Turdlings
Chapter 1
Boss
5
62
Rating
5.5
Spread
5
62
Rating
5.5
Spread

32.Tuff Twins
32.Tuff Twins
Chapter 2.5
Boss
5
61
Rating
7.7
Spread
5
61
Rating
7.7
Spread

33.Peep
33.Peep
Chapter 2
Boss
4
61
Rating
6.3
Spread
4
61
Rating
6.3
Spread

34.The Frail
34.The Frail
Chapter 2
Boss
4
61
Rating
12.6
Spread
4
61
Rating
12.6
Spread

35.Colostomia
35.Colostomia
Chapter 1.5
Boss
4
59
Rating
5.8
Spread
4
59
Rating
5.8
Spread

36.Reap Creep
36.Reap Creep
Chapter 2.5
Boss
5
59
Rating
4.5
Spread
5
59
Rating
4.5
Spread

37.Monstro II
37.Monstro II
Chapter 3
Boss
4
58
Rating
7.7
Spread
4
58
Rating
7.7
Spread

38.Carrion Queen
38.Carrion Queen
Chapter 2
Boss
4
58
Rating
5.9
Spread
4
58
Rating
5.9
Spread

39.Satan
39.Satan
Chapter 5
Final Boss
Boss
6
56
Rating
4
Spread
6
56
Rating
4
Spread

40.The Rainmaker
40.The Rainmaker
Chapter 1.5
Boss
4
54
Rating
7.7
Spread
4
54
Rating
7.7
Spread

41.Dark One
41.Dark One
Chapter 2
Boss
4
54
Rating
4.4
Spread
4
54
Rating
4.4
Spread

42.Rotgut
42.Rotgut
Boss
Corpse
4
53
Rating
14.8
Spread
4
53
Rating
14.8
Spread

43.Teratoma
43.Teratoma
Chapter 4
Boss
4
53
Rating
9.8
Spread
4
53
Rating
9.8
Spread

44.The Haunt
44.The Haunt
Chapter 1
Boss
5
52
Rating
5.1
Spread
5
52
Rating
5.1
Spread

45.The Bloat
45.The Bloat
Chapter 3
Boss
4
52
Rating
13.4
Spread
4
52
Rating
13.4
Spread

46.It Lives
46.It Lives
Final Boss
Chapter 4
Boss
6
52
Rating
7.2
Spread
6
52
Rating
7.2
Spread

47.Scolex
47.Scolex
Chapter 4
Boss
4
52
Rating
13.3
Spread
4
52
Rating
13.3
Spread

48.Famine
48.Famine
Chapter 1
Boss
5
52
Rating
8.6
Spread
5
52
Rating
8.6
Spread

49.Mega Fatty
49.Mega Fatty
Chapter 2
Boss
4
51
Rating
6.2
Spread
4
51
Rating
6.2
Spread

50.Gurglings
50.Gurglings
Chapter 1
Boss
5
51
Rating
9.2
Spread
5
51
Rating
9.2
Spread

51.Pestilence
51.Pestilence
Chapter 2
Boss
4
49
Rating
6
Spread
4
49
Rating
6
Spread

52.The Matriarch
52.The Matriarch
Chapter 4
Boss
4
48
Rating
5.8
Spread
4
48
Rating
5.8
Spread

53.The Lamb
53.The Lamb
Chapter 6
Final Boss
Boss
7
48
Rating
8.1
Spread
7
48
Rating
8.1
Spread

54.Rag Mega
54.Rag Mega
Chapter 2
Boss
4
48
Rating
11.9
Spread
4
48
Rating
11.9
Spread

55.The Fallen
55.The Fallen
Boss
4
46
Rating
8.7
Spread
4
46
Rating
8.7
Spread

56.Turdlet
56.Turdlet
Chapter 1.5
Boss
4
46
Rating
6.7
Spread
4
46
Rating
6.7
Spread

56.Fistula
56.Fistula
Chapter 2
Boss
4
46
Rating
6.7
Spread
4
46
Rating
6.7
Spread

58.Gish
58.Gish
Chapter 3
Boss
4
46
Rating
5.5
Spread
4
46
Rating
5.5
Spread

58.Death (Boss)
58.Death (Boss)
Chapter 4
Boss
4
46
Rating
5.5
Spread
4
46
Rating
5.5
Spread

58.The Wretched
58.The Wretched
Chapter 2
Boss
4
46
Rating
5.5
Spread
4
46
Rating
5.5
Spread

61.Singe
61.Singe
Chapter 2.5
Boss
5
45
Rating
8.2
Spread
5
45
Rating
8.2
Spread

62.Mom
62.Mom
Final Boss
Chapter 3
Boss
6
45
Rating
3.9
Spread
6
45
Rating
3.9
Spread

63.Hornfel
63.Hornfel
Chapter 2.5
Boss
5
45
Rating
9.4
Spread
5
45
Rating
9.4
Spread

64.Isaac (Boss)
64.Isaac (Boss)
Chapter 5
Final Boss
Boss
6
44
Rating
4.9
Spread
6
44
Rating
4.9
Spread

65.The Stain
65.The Stain
Chapter 2
Boss
4
44
Rating
11.5
Spread
4
44
Rating
11.5
Spread

66.Dingle
66.Dingle
Chapter 1
Boss
5
44
Rating
6.3
Spread
5
44
Rating
6.3
Spread

67.Widow
67.Widow
Chapter 1
Boss
5
43
Rating
6.4
Spread
5
43
Rating
6.4
Spread

68.??? (Boss)
68.??? (Boss)
Chapter 6
Final Boss
Boss
6
42
Rating
5.4
Spread
6
42
Rating
5.4
Spread

69.The Gate
69.The Gate
Chapter 3
Boss
4
41
Rating
8.7
Spread
4
41
Rating
8.7
Spread

70.Mom's Heart
70.Mom's Heart
Final Boss
Chapter 3.5
Boss
7
39
Rating
4.5
Spread
7
39
Rating
4.5
Spread

71.Chub
71.Chub
Chapter 2
Boss
4
39
Rating
5.8
Spread
4
39
Rating
5.8
Spread

72.The Beast
72.The Beast
Final Boss
Boss
Home
6
39
Rating
7
Spread
6
39
Rating
7
Spread

73.Larry Jr.
73.Larry Jr.
Chapter 1
Boss
5
38
Rating
7.1
Spread
5
38
Rating
7.1
Spread

74.Gemini
74.Gemini
Chapter 1
Boss
5
37
Rating
7.7
Spread
5
37
Rating
7.7
Spread

75.Blastocyst
75.Blastocyst
Chapter 4
Boss
4
36
Rating
6.4
Spread
4
36
Rating
6.4
Spread

75.War
75.War
Chapter 3
Boss
4
36
Rating
6.4
Spread
4
36
Rating
6.4
Spread

77.The Siren
77.The Siren
Chapter 3.5
Boss
5
35
Rating
6.6
Spread
5
35
Rating
6.6
Spread

78.Little Horn
78.Little Horn
Chapter 1
Boss
5
34
Rating
5.8
Spread
5
34
Rating
5.8
Spread

79.Monstro
79.Monstro
Chapter 1
Boss
5
34
Rating
5.1
Spread
5
34
Rating
5.1
Spread

80.The Husk
80.The Husk
Chapter 2
Boss
4
32
Rating
8.5
Spread
4
32
Rating
8.5
Spread

80.Loki
80.Loki
Chapter 3
Boss
4
32
Rating
8.5
Spread
4
32
Rating
8.5
Spread

80.Mr. Fred
80.Mr. Fred
Chapter 4
Boss
4
32
Rating
8.5
Spread
4
32
Rating
8.5
Spread

83.The Horny Boys
83.The Horny Boys
Chapter 3.5
Boss
5
31
Rating
7.5
Spread
5
31
Rating
7.5
Spread

84.Sisters Vis
84.Sisters Vis
Chapter 3
Boss
4
31
Rating
10.1
Spread
4
31
Rating
10.1
Spread

84.C.H.A.D.
84.C.H.A.D.
Chapter 2
Boss
4
31
Rating
10.1
Spread
4
31
Rating
10.1
Spread

86.Great Gideon
86.Great Gideon
Chapter 2.5
Boss
5
31
Rating
6.1
Spread
5
31
Rating
6.1
Spread

87.Brownie
87.Brownie
Chapter 3
Boss
4
29
Rating
10.2
Spread
4
29
Rating
10.2
Spread

88.Conquest
88.Conquest
Chapter 4
Boss
4
27
Rating
9.5
Spread
4
27
Rating
9.5
Spread

89.Baby Plum
89.Baby Plum
Chapter 1
Boss
5
26
Rating
8.1
Spread
5
26
Rating
8.1
Spread

90.The Shell
90.The Shell
Chapter 2.5
Boss
5
24
Rating
6.8
Spread
5
24
Rating
6.8
Spread

91.Mega Maw
91.Mega Maw
Chapter 2
Boss
4
24
Rating
9.5
Spread
4
24
Rating
9.5
Spread

92.The Duke of Flies
92.The Duke of Flies
Chapter 1
Boss
5
22
Rating
6.6
Spread
5
22
Rating
6.6
Spread

93.Big Horn
93.Big Horn
Chapter 2
Boss
4
21
Rating
7.3
Spread
4
21
Rating
7.3
Spread

94.Clog
94.Clog
Chapter 1.5
Boss
4
21
Rating
8.2
Spread
4
21
Rating
8.2
Spread

95.Dangle
95.Dangle
Chapter 1
Boss
5
20
Rating
6.3
Spread
5
20
Rating
6.3
Spread

96.The Headless Horseman
96.The Headless Horseman
Boss
4
18
Rating
6.5
Spread
4
18
Rating
6.5
Spread

97.Pin
97.Pin
Chapter 1
Boss
5
16
Rating
2.3
Spread
5
16
Rating
2.3
Spread

98.Lokii
98.Lokii
Chapter 4
Boss
4
14
Rating
7.2
Spread
4
14
Rating
7.2
Spread

99.The Forsaken
99.The Forsaken
Chapter 2
Boss
4
13
Rating
5.1
Spread
4
13
Rating
5.1
Spread

100.Lil Blub
100.Lil Blub
Chapter 1.5
Boss
4
7
Rating
3.9
Spread
4
7
Rating
3.9
Spread

101.The Hollow
101.The Hollow
Chapter 2
Boss
4
5
Rating
2.1
Spread
4
5
Rating
2.1
Spread

102.Polycephalus
102.Polycephalus
Chapter 2
Boss
4
2
Rating
2.2
Spread
4
2
Rating
2.2
Spread

103.Gurdy
103.Gurdy
Chapter 2
Boss
4
0
Rating
0.7
Spread
4
0
Rating
0.7
Spread