void OnUnitDeath(Unit* unit) override
        {
            Creature* creature = unit->ToCreature();
            if (!creature)
                return;

            switch (creature->GetEntry())
            {
                case NPC_A:
                case NPC_B:
                case NPC_C:
                case NPC_D:
                    {
                         Map::PlayerList const& players = instance->GetPlayers();
                         if (!players.isEmpty())
                            for (Map::PlayerList::const_iterator itr = players.begin(); itr != players.end(); ++itr)
                                if (Player* player = itr->GetSource())
                                    if (player->GetQuestStatus(QUESTID HERE) == QUEST_STATUS_INCOMPLETE)
                                    {
                                        player->KilledMonsterCredit(CKILLCREDITID HERE);
                                    }
                    }
                    break;
                default:
                    break;
            }
        }