hp and mp bar from 0to100 and level up from 1 to99 (301picture in total with conditions to display them)
How about using three pictures and pictute priority with picture position to display every possibile part of one bar?
The picture number determines which picture gets displayed on top of which other.
You use one picture for the empty bar at bottom.
Above that gets a colored bar for the current HP for example - a full red bar that is positioned to cover part of that bar to determine how many HP you still have.
The third picture is to cover that part of the red bar that lands outside of the black bar, because that is of course not shortened this way.
This could be the face of the actoir, or a command display or just an ornamental part of the HZD - just make sure that it is large enough to hide the red bar when it is positioned for low HP.
Additional advantage this way: you can increase the gauge when leveling by having the black bar positioned and partially hidden by the face as well.