1. **Introduction to the Game:**
Dragon City is an enchanting social network game developed by Socialpoint, in which players are transported to a fantastical world with the lofty task of breeding, raising, and training dragons. The ultimate goal is to become a Dragon Master. Players can build their own Dragon City on floating islands, fill it with farms, habitats, buildings, and a plethora of dragons.

2. **All Characters and Levels of the Game:**
The characters in Dragon City are primarily the dragons themselves, each belonging to various elements such as fire, water, earth, and many others. Each dragon is unique and can be bred with others to produce new dragons with different abilities and appearances. As for levels, the game features numerous progressional stages. Players level up by gaining experience points (XP) through feeding dragons, breeding them, and completing various quests and battles.

3. **What Attracts Users Most to the Game:**
Players are most attracted to Dragon City's vibrant graphics, the breadth of dragons available (over 1000 different species), and the depth of strategy involved in breeding the optimal dragon. The social aspect of interacting with friends, competitive PvP battles, and the joy of collecting rare and powerful dragons further enhance its appeal.

4. **Why It Is Popular:**
Dragon City's popularity stems from its engaging gameplay loop, the satisfaction of growing an empire from a single hatchling to an army of dragons, and its accessibility on multiple platforms. Its frequent updates, special events, and the sense of community among players also contribute to its enduring popularity.

5. **The Most Difficult Part of the Game:**
The most challenging aspect of Dragon City is often considered to be the breeding of the more elusive and rare dragons, which require specific combinations and a fair bit of luck. Additionally, achieving victory in the top-tier PvP arenas can be a difficult feat for many players.

6. **Strengths and Weaknesses of the Game:**
Strengths of Dragon City include its addictive gameplay, diverse range of dragons, and regular content updates that keep the game fresh. On the downside, some players feel that the game can be quite time-consuming and that progression at higher levels can become slow without in-app purchases.

7. **What Other Games Have Been Developed by the Same Developer:**
Socialpoint, the developer of Dragon City, has also created other popular social games such as Monster Legends, Tasty Town, and World Chef. Each of these games shares Socialpoint’s commitment to engaging gameplay and social interaction.