Blue Diamond, she is told to have the powers of gem emotions and is able to control gem emotions by will. But unconditionality many times Blue Diamond shares emotions with Steven while other gems aren't fazed, In the episode Reunited, Steven starts to cry Blue Diamonds tears in Garnets arms, yet Garnet is not affected. It's like Blue Diamond and Steven share a special connection as Diamonds. More proof about this in the episode Legs From Here To Home World inside Pink Diamonds ship, Blue Diamond starts to cry but yet it only affects Yellow Diamond and Steven. There have been many leaks from the show and Rebecca sugar herself, hinting about White Diamond having her main ability set on controlling other gems through the mind. If this is true and there is a true connection between the Diamonds, White Diamond would've been able to stay connected to Pink Diamonds mind through Steven willing knowing Stevens every move. Another set of proof, During the War the three Diamonds Blue, Yellow and White Diamond sent an attack on earth that was supposed to wipe every gem on the planet. Yet one of the Diamonds purposedly sabotaged the attack. We know from the episode Legs From Here To Home World. Blue Diamonds state "Oh Stars how did you even survive we blasted the planet and obliterated every gem on its surface." From this statement, we can tell Blue Diamond Supported the attack with immense intent to destroy. Yellow Diamond also would've had no reasons to purposely sabotage the attack because in Legs From Here To Home World, Yellow Diamond attack the Crystal Gems and Steven with the intent of shattering. If my original theory is correct then there is a chance White Diamond Sabotaged the attack to give Pink Diamond the best chance of survival on earth, But yet punishing her by corrupting all other gems that were affected by the blast. That would leave the message of her fake suicidal choices engraved in other gems.
Let me know all over your thought on my theroy, tell me if you think my theroy could be correct or incorrect. I hope you enjoyed this :)
- Makiey