I'm very new at C programming, and whenever I take up a language, I always write a very simple fighting game. I think I completed the game for now, and was just curious on what you all thought of the code, what I've done wrong, what I could do to improve it, and any other tips you could give me. Right off the bat, I used 4 globals, which I know is a no-no, but I can't think of another way to do it without adding more variables. Yes, this is pretty long for what it is, and I would very much appreciate any feedback thanks

Code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>


int hislife = 20;    // Enemy's life
int yourlife = 20;   // Your life

int rand_damage;     // Random damage dealt.
int damage_self;     // Damage dealt to self if superhit


int chance() {
   int to_hit = rand() % 10 + 1;
   if (to_hit >= 6) {
      return(2);
   } else {
      return(1);
   }
}

int damage() {
   int damg = rand() % 4 + 1;
   return(damg);
}

void youswing() {

   if (chance() == 2) {
      rand_damage = damage();
      hislife -= rand_damage;
      printf("Hit enemy for %d damage!\n", rand_damage);
   } else {
      printf("Missed!\n");
   }
}

void heswing() {

   if (chance() == 1) {
      rand_damage = damage();
      yourlife -= rand_damage;
      printf("Enemy hit you for %d damage!\n", rand_damage);
   } else {
      printf("Enemy missed you!\n");
   }
}


int main() {

   char input[100];     // Data inputted
   char choice;         // Input Assignment

   srand((unsigned int)time(NULL));

   while ((choice != 'Q') && (choice != 'q')) {

      if (hislife <= 0) {
         printf("Good job. He's dead. Hope you're proud.\n");
         break;
      } else if (yourlife <= 0) {
         printf("You're dead, and you suck.\n");
         break;
      } else if ((yourlife <= 0) && (hislife <= 0)) {
         printf("You killed him, but you're dead too. Such is life..\n");
         break;
      }


      printf("His life: %d - Your life: %d\n", hislife, yourlife);
      printf("(A)ttack, (S)uperhit, (Q)uit: ");
      fgets(input, sizeof(input), stdin);
      sscanf(input, "%c", &choice);

      if ((choice == 'A') || (choice == 'a')) {

         printf("\n");

         if (chance() == 1) {
            youswing();
            heswing();
         } else {
            heswing();
            youswing();
         }

         printf("\n");

      } else if ((choice == 'S') || (choice == 's')) {

         if (chance() == 2) {
            rand_damage = damage() + 3;
            hislife -= rand_damage;
            damage_self = damage() - 2;

            if (damage_self <= 0) {
               damage_self = 1;
            }

            yourlife -= damage_self;

            printf("\nYou swung a wreckless blow for %d damage, taking %d damage to yourself\n", rand_damage, damage_self);
         } else {
            damage_self = damage() - 2;

            if (damage_self <= 0) {
               damage_self = 1;
            }

            yourlife -= damage_self;
            printf("\nYou threw a completely wreckless blow, hurting yourself for %d damage!\n", damage_self);
         }

         if (chance() == 1) {
            rand_damage = damage();
            yourlife -= rand_damage;
            printf("Enemy hit you for %d damage!\n", rand_damage);
         } else {
            printf("Enemy missed you!\n");
         }

      } else if ((choice == 'Q') || (choice == 'q')) {
         printf("Goodbye\n");
      } else {
         printf("Unknown: %c\n", choice);
      }

   }

   return(0);

}