Despite their appearances, the following are not ways of change... at least, I hope not.
- Kids shows (8+?)
- Lizard (6+?)
- Missiles group (5+?)
- Body manipulator (4+?)
- Bird (3+?)
- Emperor (5+?)
The final answer is a thematic phrase.
Hint 1: (updated)
connections-puzzle is now word-property.
Hint 2: (updated)
video-games tag added.
Hint 3:
? = 3
Hint 4: (updated, minor spoiler?)
"Change/ways of change" is a hint for the video game(s) being referenced; the specific kind of change is hinted by "era,” which is also the identity of the ?.
Hint 5: (major spoilers)
Some actual ways of change include fire (4+?) and water (5+?), but not fish (4+? or 5+?) or reptile (4+? or 7+?).