A

• [+] Aliens (5)
• [+] Animated characters (3)

B

• [+] Beast Era characters (5)

C

• [+] Children of Primus
• [+] Combiners (9)
• [+] Crossovers characters

D

• [+] Deceased characters (1)
• [+] Dimension hoppers
• [+] Double agents
• [+] Drones (3)

E

• [+] European-original characters (2)

F

• [+] Fiction-only characters (5)
• [+] Functions (22)

G

• [+] Gender-switch characters
• [+] Generation 1 characters (28)

G cont.

• [+] Go-Bots franchise characters
• [+] Gods

H

• [+] Humans (9)

J

• [+] Japanese-original characters (4)

K

• [+] Kansai characters
• [+] Kre-O characters (2)

L

• [+] Letters page answerers
• [+] Live-action film series characters (3)

M

• [+] Matrix bearers

N

• [+] Nameless characters

P

• [+] Power Core Combiners Decepticons
• [+] Power Core Combiners characters (3)
• [+] Prime characters (3)
• [+] Primes

R

• [+] Rescue Bots characters (1)

R cont.

• [+] Resurrected characters
• [+] Robots in Disguise characters

S

• [+] Seekers
• [+] South American-original characters
• [+] Subgroups (26)

T

• [+] Timelines characters (1)
• [+] Toy-only characters
• [+] TransTech characters
• [+] Transformers (13)
• [+] Transformers (2010) characters (2)
• [+] Turncoats

U

• [+] Unicron Trilogy characters (3)
• [+] Unicron-related characters (3)