Raincloud

[Halewijn]

The flame -2, regen etc is also for the opponent right? Then, is the option to pay to remove corrode and burn also for the enemy?

[Zuberi]

Whenever a card's text vaguely mentions "you", assume it is talking to the controller of the card. So, when [mwcard=MWBG1J04]Raincloud[/mwcard] says "you may remove 1 Burn or Corrode" it means that the controller of Raincloud may remove 1 Burn or Corrode. Neither your opponents nor your allies receive this ability, just like they are unable to pay mana to move the Raincloud.

[Kharhaz]

But for the sake of clarity, the first line of text does apply to the opponent's cards since they are objects

[Coshade]

You are correct. You're opponent's objects also gets Flame -2, Acid -2, and Regenerate 1