MONGIL Monsterling Guide: How to Build and Evolve

What Monsterlings are and why they matter

Netmarble describes Monsterlings as a monsters core and magical essence. In gameplay terms, Monsterlings are the companion system that sits alongside your character build. Every character in MONGIL can equip up to three Monsterlings, and each Monsterling contributes an effect and a Link Chain that activates during combat.

Monsterlings are part of the main game loop. The global store listing makes collecting monsters and completing the Monster Codex a core progression goal. You tame monsters during exploration, add them to your Codex, and then use them in your team. The more Monsterlings you collect, the more options you have for building effective teams.

This guide covers how to tame, fuse, evolve, and choose Monsterlings for your characters. It also explains the changes Version 1.2 brought to the system and how Legendary Monsterlings work.

Taming and the Monster Codex

Taming is the primary way to add Monsterlings to your collection. You encounter monsters during exploration and combat throughout the game world. When you tame a monster, its Monsterling form is added to your Monster Codex. The Codex tracks every Monsterling you have ever collected, including ones you have since used in Fusion or dismantled.

The Monster Codex is more than a checklist. It shows each Monsterlings number, name, effect, and acquisition route. As of the current data, the Codex contains 165 Monsterling records, though only about 20 have fully documented effects. The rest have names and index numbers but their effect details are still being recorded by the community.

Taming does not require special items or currency. You simply encounter and defeat or capture monsters in the field. Some Monsterlings are tied to specific regions or story progression, so explore new areas as they unlock to fill out your Codex.

The Monster Codex Tracker tool on this site lets you mark which Monsterlings you own and see which ones you are missing. Use it to set collection goals and track your progress over time.

Monsterling effects and Link Chains

Every Monsterling has two combat contributions: an effect and a Link Chain. The effect is a passive bonus that activates when the Monsterling is equipped. The Link Chain is a bonus that triggers under specific combat conditions, such as hitting an elemental weakness, landing a critical hit, or using a Switch Skill.

Understanding the difference between effects and Link Chains is the key to choosing Monsterlings wisely. A Monsterlings effect benefits the character who equips it. A Link Chain benefits the whole team, often by reducing enemy elemental RES or boosting team-wide damage stats.

Here are some of the strongest Monsterling picks based on current community data. Duoxini is a strong Fire pick because both its main effect and Link Chain reduce Fire RES. Amon gives the whole team Crit Rate after repeated hits on a boss, making it one of the best general-purpose Monsterlings for longer fights. El Dorado Guardian is a strong support Link Chain pick because it raises elemental weakness damage for the team. Gulgak lowers DEF on a boss critical hit and adds a useful Lightning Link Chain, so it often fits a Sub DPS slot.

For Ice teams, Red Shadow provides Crit Damage and Ice RES reduction. Blue Shadow fits Sera and other Ice teams that want Ice damage plus Ice RES and weakness-damage support. Moon Shadow Lupe lowers Ice RES, and its Freeze Link Chain adds control utility.

For Wind teams, Nokjung adds Crit Rate after an Evasion Counter and lowers Wind RES through its Link Chain. For Earth teams, Custos pairs with El Dorado Guardian when you want an Earth team to add a DEF reduction during stagger.

The Monsterling Matcher tool on this site compares the Monsterlings you own against the roles you need. Use it to find the best available option for each of your three Monsterling slots.

Fusion: combining and upgrading Monsterlings

Fusion is the system for combining two Monsterlings into a new one. When you fuse, the result can be a higher-tier Monsterling with better effects and Link Chains. Fusion also has a chance to unlock new traits on the resulting Monsterling, which are passive bonuses that further enhance its combat contribution.

Before Version 1.2, Fusion outcomes were partly random, and Mutant Monsterling synthesis had a failure chance. Version 1.2 changed this by adding guaranteed success for Mutant Monsterling synthesis. This means you can now plan your Fusion path with more confidence, knowing that a specific combination will produce the result you want.

To use Fusion effectively, start with Monsterlings you do not plan to equip. Use them as Fusion material to upgrade the Monsterlings you actually use. Focus on the Monsterlings that directly benefit your main DPS carry first, then work on support Monsterlings.

When multiple unlocked traits of the same grade exist, the Trait Material Probability Information UI may only display one. This is a known display issue; the actual Fusion mechanics still account for all unlocked traits. Check the in-game Fusion screen carefully before confirming a combination.

Trait reset, enhancement, and Version 1.2 changes

Version 1.2 added two important features to the Monsterling system: trait reset and trait enhancement. Trait reset lets you remove a trait from a Monsterling and return it to a blank state. Trait enhancement lets you strengthen an existing trait to increase its effect.

These features give you much more control over your Monsterling progression. Before Version 1.2, a bad trait roll on a Monsterling was permanent. Now you can reset it and try again. Trait enhancement lets you invest materials into a good trait to make it even stronger, without risking it through Fusion.

Use trait reset when a Monsterling has a trait that does not match your team composition. For example, if a Fire Monsterling rolled a Wind RES reduction trait and your team is Fire-focused, reset the trait and look for one that benefits Fire damage.

Use trait enhancement when a Monsterling has a trait that directly benefits your carry. Enhancing a Crit Rate trait on a Monsterling that your main DPS uses is one of the best material investments you can make in the current version.

Legendary Monsterlings were also added in Version 1.2. They come from the Twinkling Starlight currency earned in Legendary Conquest. Each contract consumes Starlight and has a chance to build Trust. Filling the first Trust gauge grants the Legendary Monsterling, and later contracts raise its tier. Legendary Monsterlings can be equipped to multiple characters at once and cannot be dismantled or used as Fusion material, so there is no way to accidentally waste one.

Choosing Monsterlings for your team

The right Monsterlings for your team depend on your characters element, role, and the content you are clearing. Here is a simple framework for choosing.

For your main DPS carry, equip Monsterlings that reduce the enemys elemental RES for your carrys element. This is the single biggest damage increase from the Monsterling system. Duoxini for Fire, Red Shadow or Blue Shadow for Ice, Gulgak for Lightning, and Nokjung for Wind are the strongest picks in each element.

For your support characters, equip Monsterlings that provide team-wide bonuses. Amon (Crit Rate for the team), El Dorado Guardian (elemental weakness damage for the team), and Fiend (Super Armor and weakness damage for Fire teams) are the top support picks. These Monsterlings benefit the whole team, not just the character they are equipped on.

For the third Monsterling slot, consider what your team is missing. If your carry already has good RES reduction, add a Monsterling that boosts a secondary stat like Crit Damage or DEF reduction. If your team lacks survivability, look for Monsterlings with defensive Link Chains.

Do not equip Monsterlings based on name rarity alone. A lower-tier Monsterling with the right elemental RES reduction is more valuable than a higher-tier Monsterling with a generic effect. Check the Monster Codex entries on this site for effect details before making your choice.

1. Open the Monster Codex Tracker and mark the Monsterlings you own.
2. Identify your main DPS carrys element.
3. Find Monsterlings that reduce that elements RES on the enemy.
4. Equip the best RES reduction Monsterling in the first slot.
5. Add a team-wide support Monsterling (Amon, El Dorado Guardian, or Fiend) in the second slot.
6. Fill the third slot with a Monsterling that covers your teams biggest gap.
7. Use Fusion and trait enhancement to upgrade your equipped Monsterlings over time.

Building your Monsterling collection over time

Monsterling progression is a long-term goal. You will not have every strong Monsterling on day one, and that is fine. Start with the Monsterlings you have, focus on the ones that benefit your main carry, and use Fusion to upgrade the rest.

The community spreadsheet maintained by Yridyl tracks Monsterling effects, Link Chains, and recommended pairings. It is the most detailed public source for Monsterling data and is regularly updated. Use it alongside the Monster Codex on this site to plan your Fusion and trait investments.

After a new version update, check whether new Monsterlings were added or existing ones were changed. Version 1.2 added Legendary Monsterlings and changed the Fusion system. Future versions may add new Monsterling types or rebalance existing effects. Keep your Monsterling plan flexible and adjust it when the game changes.

Frequently asked questions