Cheat Engine

[Blunderbread]

Hi, here is a picture to explain what I tried to do at first. My goal is to compare my health address to rdi which holds the health address what is currently taking damage. I'm doing this to filter my health out and set everything else to 0, effectively giving me godmode. I've made this work on several games but the current one I'm working on is giving me trouble.

I ended up moving rdi to rax and using that as a cmp (and yes, I remembered to pushf and push rax then pop rax and popf), and it made enemies spawn but stand still and not be able to take damage. even after disabling the script, the behavior persists and shooting one of these frozen enemies instantly crashes the game.

Does someone know something about rdi that I don't? Thanks for your help in advance

[panraven]

The symbol _pb is not defined within the script,
if it also not defined outside the script,
the assembler instruction will not compile as _pb is not known.

Also if _pb as an number has more that 32bit,
it will neither compiled as only a few x86-64 instruction can
has immediate number value more than 32bit. (It could compile if
the number used as an memory pointer and within 2g distance
from current address, RIP addressing, eg. cmp rdi,[_pb] )
May use a cpu register to hold the _pb value and do the compare,ie.

[Blunderbread]

Thank you for the insight. I pushed _pb into rax and now the game seems to behave as it did before where enemies spawn in and freeze in place while not taking damage. When I disable this script, shooting one of the enemies crashes the game.

This may have more to do with me finding a good target, with rdi persisting even though other enemies are taking damage. I'll look more into it later; I just think it's weird how disabling the script allows the strange behavior to persist and crash the game

[Blunderbread]

Update for anyone who was curious: There was definitely an issue with RDI in the particular circumstance that I was trying.

The initial issue was fixed when converting the playerbase (denoted as _pb) from 64 bit to 32 bit by using mov rax, _pb.

The subsequent issues appeared because RDI does not uniquely reference the playerbase when the player was taking damage. I ended up taking a stab at the 'godMode' variable that the developers ever so kindly left in the game; by using the assembly to write a 1 to the godMode flag prior to initializing controls on the game and turning it off, I made myself invincible but also made the first 2 or 3 enemies that spawn at the same time as the player invincible. It wasn't a big deal after clearing the first round since not all enemies needed to be cleared. Additionally, setting [rdi] to 0 instead of xmm5 killed existing enemies instantly but also prevented new ones from spawning (and giving money/experience), and interestingly prevented me from picking up items.

The game is RoR2 which has fairly recently come out of early access on steam; great game btw. I won't say the game name directly because I don't want the developers to stumble upon it directly and patch it all, but you can google RoR2 and know what I mean.