HP hacks can be done the thing is it's hard. Cheat engine can do it. I've messed around with the values and the thing is you can keep regenerating yourself to 100 HP and 100 AP but if they are using a 1 shot kill gun it can regenerate fast enough. EX You have 100 HP and you run into someone if they click mouse fast enough your health can't keep up and you die. It's easy to do and Please don't beg for hacks Mess around with stuff and figure it out.
mostly i believe these values are now serverside, which means albeit the values are changed (for example u memory edited ur GP/EXP value)
they effects may be visible but when you try to spend that 999999 GP it will show insuffecient funds and refuse ur purchase lol.
same goes with the health locking hacks, where u lock ur health/ammo/armor to a certain value it may display 999 health but infact ur the same as everyone else.
the only health hack atm requires you to avoid opposing bullit fire for a short period of time and let your health regen quickly.
but i am prolly wrong lol.
but for sure there are new values that are lockable but u will haveto find them urself or pay for a VIP hack and all the works done for you
i don't think its server sided, i got hit by ak two times, and my hp dropped to 20+ and CE brought it back to 100, then i got hit by a grenade nearby and my hp dropped to 50+ and CE brought it back to 100 again. i should have died already. It is probably either CE cannot update the values fast enough OR the client compares your client hp to the server's hp.
 my bad it is server sided (i think)