I haven't been able to find answers to these that either exist or are reliable so I'm hoping to get clarification on how this works.

For the questions, we're going to assume the Champion in question has 20,000 Max Health normally and currently has 50% of their Max HP destroyed.

1. Is the Champion treated as being "Full HP" with 10,000 Health since that is their current maximum OR if you have destroyed HP are you NEVER treated as "Full HP"

2. If damage is based on Max HP, is it going off of the current limit of 10,000 or is it calculated off of the 20,000?

3. If an ability says it has a bonus against a target with 50% HP or less, does it work against the Champion OR would they have to be below 5000 HP since their current "Max" is 10,000?

4. Same as previous question, but with a passive like Rotos's. If 50% of his max hp is destroyed will his passive still protect him and cap hits at 5000 HP or not?

I think it's pretty clear why this is confusing and I'm very interested to find out how this works.

Lastly, one quick thing about Head of Decay: Why does it destroy HP from heals that aren't actually restoring health BUT for Miracle Heal and Curing Sets, they ONLY restore Destroyed HP in the amount of the actual healing needed? So like, say it's a 20% heal restore and the character is missing 8000 health and the heal value is 20000, miracle heal only restore 1600 HP and not 4000 HP