Universal Tower Defense X (UTDX) Update 4.0 is one of the biggest updates the game has received, introducing 24 new units across multiple rarities, including Boundless, Secret, Unrivaled, Mythic, Exclusive, and Synchro units. With so many new characters arriving at once, it’s easy to lose track of where each one comes from.
If you’re wondering which game mode you should grind or which units require evolutions, this guide covers every new unit added in Update 4.0 and how to unlock them.
Universal Tower Defense X Update 4.0 — How to Get Every New Unit
The update introduces units from several different sources, including:
- Evolutions
- Raids
- Legend Stages
- Universal Tears
- Extraction Missions
- Summer Capsules
- Banner Summons
- Hollow vs Reapers Event
Since every unit comes from a different activity, it’s much faster to know exactly where to farm before spending your time.
Boundless Units
These are among the strongest units introduced in the update.
Ichigo (Moonless Sky)
How to unlock
Ichigo (Moonless Sky) is obtained by evolving Ichigo Rage.
To evolve him, you’ll need the required evolution materials, which are primarily earned through the new Rift/Universal Tear content.
If you already own Ichigo Rage, you’re halfway there.
Yuhaba (Boundless)
Yuhaba’s Boundless version is also obtained through evolution.
First you’ll need to unlock The King, then evolve him into Yuhaba’s Boundless form using the required evolution materials.
Secret Units
Several Secret units were added in Update 4.0.
Simon
Location
- Legend Mode
- Beast Desert
- Act 3
Simon can be earned by clearing the Beast Desert Legend stages, with Act 3 being the stage that drops him.
Ice Cream (Rukia)
Ice Cream (Rukia) is unlocked by evolving Ruka.
If you already own the base version, simply gather the required evolution materials and complete her evolution.
Flame Captain (Yamamoto)
Location
- Reaper City Raid
- Act 5
The final act of the Reaper City Raid is where you’ll want to farm if you’re trying to unlock Yamamoto.
Light Prince Ascension
This unit is earned through the Hollow vs Reapers event.
Continue progressing through the event until you reach the required milestone or reward tier.
The King
The King drops from the Moonless Sky Universal Tear.
Once obtained, he can later be evolved into Yuhaba’s Boundless version.
One helpful improvement in Update 4.0 is that Universal Tears are no longer locked behind a single rotating schedule, making farming much more convenient.
Human Spider
Location
- Crime Fighting Extraction
This limited-time Extraction mission contains several superhero-themed units.
Iron Man
Also obtained from the Crime Fighting Extraction event.
Venom
Like Human Spider and Iron Man, Venom is another reward from the Crime Fighting Extraction mode.
If you’re farming this event, you’ll naturally have a chance at all three units.
Persona Event Units
The Golden Palace Extraction introduces several new characters.
These include:
- Trickster
- Ann
- Feline
- Cranium
All four units can be obtained by farming the Golden Palace Extraction mode.
If you’re already running this stage, you’ll be making progress toward multiple units at the same time.
Unrivaled Unit
Grammy (Visionary Evolution)
Grammy is the new Unrivaled unit added in Update 4.0.
To obtain him, you’ll first need Visionary, then evolve him into Grammy.
Because Unrivaled units are among the rarest in the game, expect this to be one of the longer grinds.
Summer Event Exclusive Units
The Summer Event introduces two limited Exclusive units.
Ashura
Obtained from:
- Summer Capsules
Firefly
Also available through:
- Summer Capsules
Summer Capsules can be opened using the Summer Event currency.
You’ll also receive other event rewards, including Summer Crates, while participating.
Banner Units
Several new units were added to the summon banner.
These include:
- Cat Captain
- Bloody Captain Uno
- Corpse Maiden / Zombie Apostle (depending on current naming)
- Additional featured banner units
If you’re planning to summon, make sure you’re pulling during the correct banner rotation.
Zombie Apostle / Corpse Maiden
One confusing part of the update is the naming.
In-game, some players have noticed that Corpse Maiden appears to correspond with Zombie Apostle in the update notes.
Whether this is simply a naming inconsistency or a future change, the current Banner is where you’ll obtain this character.
Synchro Units
Update 4.0 also introduces two Synchro combinations.
Human Spider + Iron Man
These two units form one of the new Synchro pairings.
Spider-Man + Venom
The second Synchro combination uses Spider-Man and Venom.
Since both are obtained from Crime Fighting Extraction, you’ll naturally work toward this Synchro while farming the event.
UTDX Update 4.0 adds a huge variety of new units, but most of them are tied to specific game modes rather than random luck alone. Before jumping into endless farming, decide which unit you want first and focus on the activity that drops it. This approach is much more efficient than bouncing between raids, extractions, and events without a clear plan.
If you’re aiming for 100% completion, prioritize the limited-time Summer Event and Crime Fighting Extraction while they’re available, then work through the permanent content like Legend Mode, Raids, Universal Tears, and Evolutions at your own pace.