Like we already allow for damage particles, unit particles now allow you to use minHp / mapHP. The code has been pushed to the develop branch
example:
<skill>
<type value="produce"/>
<name value="produce_skill"/>
<ep-cost value="0" />
<speed value="300" />
<anim-speed value="300" />
<animation path="models/dungeon1.g3d" minHp="1" maxHp="160"/>
<particles value="true">
<particle-file path="no_particles.xml" minHp="1" maxHp="5998" minmaxEnabled="true"/>
<particle-file path="fire_particles.xml" minHp="5999" maxHp="6000" minmaxEnabled="true"/>
</particles>
<sound enabled="false" />
</skill>