Example of a monster system

Monster.h

struct MonsterDefinition
{
	const char * name;
	uint16_t defaultHP;
	uint16_t defaultAttack;
	uint16_t defaultDefence;
	// etc
};

class Monster
{
private:
	const MonsterDefinition * type;
	uint16_t hp;
public:
	Monster(const MonsterDefinition & type)
		: type(&type)
	{
		this->hp = pgm_read_word(&type->defaultHP);
	}

	bool isAlive(void)
	{
		return this->hp != 0;
	}

	void takeDamage(uint16_t amount)
	{
		this->hp = (this->hp > amount) ? this->hp - amount : 0;
	}

	void heal(uint16_t amount)
	{
		this->hp = (this->hp + amount > this->hp) ? this->hp + amount : 0xFFFF;
	}
	
	const char * getName(void)
	{
		return reinterpret_cast<const char *>(pgm_read_word(&this->type->name));
	}
	
	const __FlashStringHelper * getPrintableName(void)
	{
		return reinterpret_cast<const __FlashStringHelper *>(pgm_read_word(&this->type->name));
	}
};

const char monsterName0[] PROGMEM = "Slime";
const char monsterName1[] PROGMEM = "Skeleton";
const char monsterName2[] PROGMEM = "Dave";
const char monsterName3[] PROGMEM = "Pharap";

const MonsterDefinition monsterDefinitions[] PROGMEM =
{
	{ monsterName0, 10, 5, 20 },
	{ monsterName1, 20, 15, 5 },
	{ monsterName2, 1, 0, 0 },
	{ monsterName3, 1500, 4500, 8000 },
};

enum class MonsterId : uint8_t
{
	Unknown,
	Slime,
	Skeleton,
	Dave,
	Pharap,
};

bool spawnMonster(MonsterId id, Monster & monster)
{
	if(id == MonsterId::Unknown)
		return false;
		
	const MonsterDefinition * = &monsterDefinitions[static_cast<uint8_t>(id) - 1];
	monster = Monster(*monsterDefinition);
	return true;
}