How to Defeat the Oceanid in Genshin Impact: A Comprehensive Guide

The Oceanid, Rhodeia of Loch, is a challenging world boss in Genshin Impact that players must defeat to ascend certain characters, particularly Hydro characters like Mona and Kokomi. Located in the Bishui Plain area of Liyue, this fight is unique because you don’t directly attack the Oceanid herself. Instead, you battle her Hydro Mimics, which come in various forms and possess different attack patterns. This guide will provide a detailed breakdown of the Oceanid’s abilities, the best strategies for defeating her, recommended team compositions, and tips for maximizing your efficiency.

## Understanding the Oceanid

Before diving into the battle, it’s crucial to understand what makes the Oceanid a formidable opponent. Here’s a detailed overview:

* **Indirect Combat:** As mentioned earlier, you never directly attack the Oceanid. Rhodeia remains on her platform and summons Hydro Mimics to fight for her.
* **Hydro Mimics:** These are the key to defeating the Oceanid. They come in several forms, each with unique attacks and elemental affinities:
* **Waterfowl (Cranes and Ducks):** Fly around and dive bomb, dealing Hydro damage.
* **Boar:** Charges at you dealing Hydro damage.
* **Squirrel:** Rapidly deals Hydro damage with its attacks.
* **Crab:** Slow, but high HP. Deals Hydro damage and can create bubbles.
* **Lizard:** Climbs onto pillars and shoots Hydro projectiles.
* **Raptor (Falcon):** Flies around and swoops down, dealing Hydro damage.
* **Frog:** Jumps into the air and slams down, dealing significant Hydro damage.
* **Weasel:** Teleports and deals quick Hydro damage.
* **Rising Water Level:** During the battle, the water level in the arena will occasionally rise, reducing the available platform space. If you fall into the water, you’ll take continuous Hydro damage.
* **Wrathful Rhodeia:** When you defeat a certain number of Mimics without taking down Rhodeia completely, she will become enraged. This phase is signaled by a dialogue cue. During this phase, she will unleash a powerful wave attack across the arena. You need to stand on the pillar to avoid damage.
* **Revival Platforms:** If a character falls in battle, they cannot be revived using food. Instead, a revival platform will appear after a certain time. Keep an eye out for these platforms to revive your fallen teammates.
* **Hydro Application:** The Oceanid and her Mimics constantly apply Hydro, making you susceptible to the Electro-Charged and Frozen reactions.

## Preparing for the Battle

Proper preparation is key to ensuring a smooth and efficient Oceanid fight. Here’s what you should consider:

* **Team Composition:** This is arguably the most crucial aspect. Given the Oceanid’s Hydro-heavy nature, Pyro, Cryo, and Electro characters are highly effective. Specifically:
* **Pyro:** Pyro characters can Vaporize Hydro-infused enemies, dealing significant damage. Consider characters like Diluc, Hu Tao, Yoimiya, or Bennett.
* **Cryo:** Cryo characters can Freeze enemies, rendering them immobile and vulnerable. Ganyu, Ayaka, Kaeya, or Rosaria are good choices.
* **Electro:** Electro characters can Electro-Charge enemies, dealing continuous damage over time. Raiden Shogun, Yae Miko, Fischl, or Beidou can be very effective.
* **Healer/Shield:** A reliable healer or shielder is essential for survivability. Bennett, Jean, Barbara (though she applies Hydro which can be problematic), Diona, or Zhongli are all excellent choices. Bennett is often considered the best due to his healing and ATK buff.
* **Character Levels and Talents:** Ensure your characters are appropriately leveled and that their talents are upgraded, especially those related to their Elemental Skills and Bursts. Aim for at least level 70+ for your main DPS and support characters.
* **Weapons and Artifacts:** Equip your characters with appropriate weapons and artifacts. Focus on ATK, Crit Rate, Crit DMG, and Elemental Mastery for your DPS characters. Energy Recharge is also important for characters who rely on their Elemental Bursts. Good artifact sets include:
* **Crimson Witch of Flames (Pyro DPS):** Increases Pyro damage and Vaporize/Melt damage.
* **Blizzard Strayer (Cryo DPS):** Increases Cryo damage and Crit Rate against Frozen enemies.
* **Thundering Fury (Electro DPS):** Increases Electro damage and triggers Electro-Charged/Superconduct/Overload reactions more often.
* **Noblesse Oblige (Support):** Increases Burst damage and provides an ATK buff to the team.
* **Food and Potions:** Stock up on helpful food buffs and potions. Consider:
* **ATK-boosting food:** Adeptus’ Temptation, Jade Parcels, or similar dishes to increase your damage output.
* **Crit Rate/DMG food:** Delicious Tea Break, or similar dishes to improve your critical hit stats.
* **Stamina food:** Northern Apple Stew or similar dishes to help manage stamina for dodging and sprinting.
* **Hydro Resistance Potion:** If you find yourself struggling with Hydro damage, a Hydro Resistance Potion can be helpful.
* **Understanding Elemental Reactions:** Brush up on your knowledge of Elemental Reactions, particularly Vaporize (Pyro + Hydro), Freeze (Cryo + Hydro), and Electro-Charged (Electro + Hydro). Knowing how these reactions work will allow you to maximize your damage output.

## Battle Strategy: Step-by-Step Guide

Now, let’s break down the battle into a step-by-step guide:

**Phase 1: Initial Mimics**

1. **Identify the Mimics:** The Oceanid will summon a wave of Hydro Mimics. Pay attention to which Mimics appear first. Generally, the faster-moving ones like the Weasel and Squirrel will approach you quickly, while slower ones like the Crab will take longer.
2. **Prioritize Targets:** Focus on taking down the Mimics that pose the greatest threat or are the most difficult to hit. Waterfowl and Raptors can be annoying due to their aerial movement, while Frogs and Crabs can deal significant damage if you’re not careful.
3. **Utilize Elemental Reactions:** Consistently apply Pyro, Cryo, or Electro to trigger reactions. Vaporize with Pyro characters is especially effective for dealing burst damage. Freeze with Cryo characters can control the battlefield and make it easier to hit the Mimics.
4. **Manage Stamina:** Dodging is crucial to avoid taking unnecessary damage. Don’t deplete your stamina completely, or you won’t be able to dodge incoming attacks.
5. **Stay Mobile:** Avoid staying in one place for too long. The Mimics can quickly surround you, making it difficult to escape their attacks.

**Phase 2: Rising Water Level**

1. **Be Aware:** Periodically, the water level in the arena will rise, reducing the available platform space. This can be dangerous if you’re not paying attention.
2. **Relocate Quickly:** As the water level rises, move to a higher platform to avoid falling into the water. Falling into the water will cause continuous Hydro damage and significantly hinder your movement.
3. **Adjust Strategy:** The reduced platform space can make it more difficult to dodge attacks. Adapt your strategy accordingly and prioritize staying alive.

**Phase 3: Wrathful Rhodeia**

1. **Recognize the Warning:** Rhodeia will announce her anger with a dialogue cue, indicating that she is about to unleash a powerful wave attack.
2. **Seek Shelter:** A single platform will rise in the center of the arena. Immediately move to this platform. Standing on the platform is the *only* way to avoid the full brunt of the attack.
3. **Prepare for the Next Wave:** After the wave attack, the water level will usually return to normal, and Rhodeia will summon another wave of Mimics. Prepare to resume the battle.

**Phase 4: Repeat and Adapt**

1. **Repeat the Process:** Continue defeating the Mimics, managing the rising water level, and avoiding Rhodeia’s wrathful attacks.
2. **Adapt to Mimic Combinations:** The combinations of Mimics that Rhodeia summons will vary. Adjust your strategy based on the specific Mimics you’re facing. If she summons a lot of Waterfowl, prioritize characters with ranged attacks. If she summons a lot of Frogs, be prepared to dodge their slam attacks.
3. **Manage Character Health:** Keep an eye on your characters’ health and use your healer or shielder as needed. Don’t be afraid to use food buffs if you’re struggling to stay alive.

## Specific Mimic Strategies

Here’s a more detailed breakdown of how to deal with each type of Hydro Mimic:

* **Waterfowl (Cranes and Ducks):** These are annoying due to their aerial movement. Use ranged characters or characters with skills that can hit airborne targets. Fischl’s Oz, Ganyu’s Charged Attacks, and Yoimiya’s Elemental Skill are all effective.
* **Boar:** These charge at you in a straight line. Dodge to the side to avoid their charge, then attack them while they’re vulnerable.
* **Squirrel:** These deal rapid Hydro damage. They are relatively fragile, so focus them down quickly. Cryo is effective for freezing them, making them easier to hit.
* **Crab:** These are slow but have high HP. Use Pyro characters to Vaporize them and deal significant damage. Be careful of their bubble attacks, which can trap you.
* **Lizard:** These climb onto pillars and shoot Hydro projectiles. Use ranged characters to take them down from a distance. Prioritize them, as their projectiles can be disruptive.
* **Raptor (Falcon):** Similar to Waterfowl, these fly around and swoop down. Use ranged attacks or skills that can hit airborne targets.
* **Frog:** These jump into the air and slam down. Watch for their telegraph and dodge just before they land. They are vulnerable after their slam attack.
* **Weasel:** These teleport and deal quick Hydro damage. They can be difficult to hit. Try to predict their teleport locations and use AoE attacks to hit them.

## Recommended Team Compositions

Here are a few sample team compositions that can be effective against the Oceanid:

* **Vaporize Team:**
* **Main DPS:** Diluc, Hu Tao, or Yoimiya
* **Sub-DPS:** Xingqiu or Yelan (for Hydro application)
* **Support:** Bennett (for healing and ATK buff)
* **Flex:** Sucrose or Kazuha (for Elemental Mastery buff and grouping enemies)

* **Freeze Team:**
* **Main DPS:** Ganyu or Ayaka
* **Sub-DPS:** Rosaria or Kaeya (for Cryo application)
* **Support:** Barbara or Kokomi (for healing and Hydro application)
* **Flex:** Venti or Kazuha (for grouping enemies)

* **Electro-Charged Team:**
* **Main DPS:** Raiden Shogun or Yae Miko
* **Sub-DPS:** Fischl or Beidou (for Electro application)
* **Support:** Barbara or Kokomi (for healing and Hydro application)
* **Flex:** Sucrose or Kazuha (for Elemental Mastery buff and grouping enemies)

* **Budget Team:**
* **Main DPS:** Xiangling (Pyro)
* **Sub-DPS:** Kaeya (Cryo)
* **Support:** Barbara (Healer – Hydro, be mindful of the Hydro application)
* **Flex:** Lisa (Electro)

## Tips and Tricks for Success

* **Learn Mimic Patterns:** The more you fight the Oceanid, the more familiar you’ll become with the Mimics’ attack patterns. This will allow you to anticipate their attacks and dodge more effectively.
* **Prioritize Survival:** Don’t get greedy with your attacks. Focus on staying alive first and dealing damage second. A dead DPS is no DPS.
* **Use Elemental Sight:** Use Elemental Sight to identify the elemental aura on the Mimics. This can help you plan your attacks and reactions more effectively.
* **Pay Attention to Audio Cues:** The Oceanid and her Mimics have distinct audio cues for their attacks. Listen carefully to these cues to anticipate their movements.
* **Don’t Be Afraid to Experiment:** Try different team compositions and strategies to find what works best for you. The Oceanid fight can be challenging, but it’s also a great opportunity to experiment and improve your skills.
* **Co-op Mode:** If you’re struggling to defeat the Oceanid solo, consider playing in co-op mode with friends or other players. Having additional teammates can make the fight much easier.

## Common Mistakes to Avoid

* **Ignoring the Rising Water Level:** This is a common mistake that can lead to unnecessary damage and even death. Always be aware of the water level and relocate quickly when it rises.
* **Not Prioritizing Targets:** Don’t just attack the closest Mimic. Focus on taking down the ones that pose the greatest threat or are the most difficult to hit.
* **Running Out of Stamina:** Managing your stamina is crucial for dodging attacks. Don’t deplete your stamina completely, or you’ll be unable to dodge when you need to.
* **Using Only One Element:** Relying on only one element can make the fight much more difficult. Utilize Elemental Reactions to maximize your damage output.
* **Forgetting to Heal:** Don’t forget to heal your characters when they take damage. A reliable healer is essential for survivability.

## Rewards for Defeating the Oceanid

Defeating the Oceanid rewards you with various items, including:

* **Varunada Lazurite Fragments, Slivers, Chunks, and Gemstones:** These are ascension materials used for Hydro characters.
* **Cleansing Heart:** This is a character ascension material specifically dropped by the Oceanid.
* **Adventurer’s Experience, Wanderer’s Advice, and Hero’s Wit:** These are character experience materials.
* **Artifacts:** You can obtain various artifacts, including Instructor, The Exile, and Berserker sets.
* **Mora:** The game’s primary currency.

## Conclusion

The Oceanid is a challenging but rewarding boss in Genshin Impact. By understanding her abilities, preparing your team effectively, and following the strategies outlined in this guide, you can defeat her and obtain the necessary materials to ascend your Hydro characters. Remember to be patient, adapt to the different Mimic combinations, and don’t be afraid to experiment. Good luck, Traveler!