Thank you, Welshylf, for your speedy reply.
I followed your instruction:
Infinity blade 3; ipad air ios 11.2.6
1. Backup app data with iMazing;
2. Immediately restore app data with iMazing;
3. Change infinityblade3.imazingapp to infinityblade3.zip;
4. Edit;
*I may have done something wrong here, I've tried:
- copied and pasted 'documents' and 'library' folders from cheat folder to extracted infinityblade3.zip folder, replaced files;
- deleted 'documents' and 'library' in extracted infinityblade3.zip folder, copied and pasted 'documents' and 'library' folders from cheat folder;
- copied and pasted files from sub-folders of cheat folder to respective folders in extracted infinityblade3.zip folder, replaced files.
5. Compress edited folders into infinityblade3.rar, rename to infinityblade3.imazingapp;
6. Restore app data with iMazing.
This message still shows:
"has not been acquired by the Apple ID
*myappleid*
iMazing can only download apps which you have already purchased or acquired from the App Store. You can also try to sign in with another Apple ID"
Updated: I'm not sure why but when I compress the edited folders, I change archive format to zip, file name is: infinityblade3.imazingapp, I can restore app data without the message shows up. Unfortunately, in the end the save game doesn't work, the game automatically rolls back to new game/new start. Maybe because the cheat is outdated and no longer works on ios 11.2.6, infinity blade 1.4.4?