edit: oops user above got here before me

Each entity has 100 skill variables assigned to them that you can use for whatever you want. You can access them like this

my.skill[0] = 100 //health
my.skill[2] = 3 //lives
my.skill[99] = 50 //credits

you also have access to FLAG1 - FLAG8, and string1 - string2

-(optional)-
you can also create 'synonyms' for the skills to name them in a way that makes them easier to use

#define HEALTH skill[2] //somewhere in the beginning of your script

my.HEALTH = 100

Hope that helps