How to Get Undine in Catch a Monster (2026)

Undine is one of the most powerful monsters in Catch a Monster, forming the backbone of the current endgame meta alongside Eclipse Knight. Despite what many new players assume, Undine cannot be caught in the wild — it is exclusively available through Rift content. This guide explains exactly how to get it.

Undine vs. Tidevex — Why Undine is Better

Many players wonder whether to bother getting Undine when they already have a high-rank Tidevex. The community consensus is clear:

Undine B-rank > Tidevex A-rank in actual combat performance.

Here is why: Undine has a superior skill set: Its stun ability is one of the best in the game, controlling bosses and letting your team deal damage safely Tideland Island content: Undine makes Tidevex and Red Rift content significantly easier once you have it Tidevex max rank from wild: A-rank. Undine from Rifts can also reach A-rank but with better starting stats

Bottom line: If you can get Undine, prioritize it over stacking Tidevex.

How to Get Undine

Undine is obtained inside a Rift — either a Red Rift or a Tideland Rift.

Method 1: Red Rift (Recommended)

Red Rifts contain Undine, Eclipse Knight, and Mechavolt.

Steps:

1. Get Red Rift Portals — buy up to 10 per week from the Spire Tower Shop
2. Open a Red Rift (in a Private Server with 2–3 players for lower boss HP)
3. Defeat Mechavolt (9–13 billion HP, scales with player count)
4. Undine may appear as the catchable monster after the Rift Boss dies

Pro Tip: Use a Pet Snack + Ripple Ball for 100% catch rate on Undine. (Pet Snack = +200% catch rate for 5 minutes; Ripple Ball is a standard mid-tier ball.)

Method 2: Tideland Rift (Alternative)

Tideland Rift and Tideland Rift III are accessible from Tideland Island and also contain Undine.

Easier boss than Mechavolt — suitable for mid-game players Tideland Rift III is the harder variant with better rewards Access via asking in Discord for a Tideland Rift carry if you are not strong enough solo

Method 3: Find a Carry

If you cannot defeat the Rift Boss with your current team:

1. Post in the official Discord #chat channel: "LF carry Tideland/Red Rift"
2. Strong players regularly offer free carries in exchange for you providing the portals
3. You deal a small amount of damage to qualify for loot, the carry does the rest

Farming Tidevex (For Vitalium Stones)

Even after you have Undine, you may still need to farm Tidevex for Vitalium Stones — a key material for the Lunavox evolution.

Tidevex spawns on Tideland Island Requires Level 35–55 to farm efficiently; Level 60+ for solo Vitalium Stones have a chance to drop with each kill Server hop for fresh Tidevex respawns (~15 minute timer)

Note on Lunavox (Feb 2026): The Lunavox evolution (Noctane → Lunavox) currently has several bugs including a broken taunt and dealing 0 damage with its first skill. Many community members recommend waiting for a patch before spending Vitalium Stones.

Best Undine Rank to Aim For

Start with whatever rank you catch in the Rift. If it is C-rank, fuse 5 C-ranks into a B-rank using the Fusion Station.

Undine in the Best Teams

For Rift portals and carrying, see Red Rift Guide. For Eclipse Knight, see Eclipse Knight Guide.