Undertale Powers

Become one of 36 playable UNDERTALE and DELTARUNE characters, explore the Underground, enter Dark Worlds and unlock powerful transformations through survival gameplay.

Summon overhead Gaster Blasters, raise bones from the ground, wield Chara’s Real Knife or become the enormous Omega Flowey. Every playable character has a custom 3D model, animated abilities and a character-inspired entrance.

Explore alone, fight mobs, challenge friends or form an alliance to take on bosses together.

Explore the Underground

Craft a Soul Compass and begin your adventure in the Ruins. Travel through Snowdin, Waterfall, Hotland, the True Lab and New Home, discovering residents, puzzles and boss encounters along the way.

The adventure includes 12 districts with 36 connected new rooms, alongside the original hubs and boss arenas.

• Challenge 36 NPC boss encounters with custom models, warning patterns and character-specific attacks.
• Defeat or SPARE bosses to obtain their Transformation Souls.
• Use transformation souls to learn playable forms permanently.
• Rest at SAVE shrines and choose your learned characters through the Soul Journal.
• Collect six human soul fragments and complete Asriel’s encounter to unlock Omega Flowey.
• Build your own saved Mercy, Resolve or Judgment route.
• Complete character training courses, earn mastery accessories and challenge Boss Rush.

Areas generate once, preserving your builds and emptied chests when you return. Leaving the adventure returns you to your original entry location.

Talking NPCs and Different Puzzles

Meet 27 peaceful residents with character portraits, original conversations and Undertale-inspired typewriter dialogue.

Ask for puzzle hints, learn about the neighbourhood or complete exploration tasks. Discover the local rooms, meet their residents and solve their puzzle to earn supplies, soul essence and a secret-encounter clue.

Each district has its own physical puzzle:

• Follow a faded leaf map through the Ruins.
• Change neighbouring switches in Papyrus’ snow puzzle.
• Align Waterfall’s bridge flowers.
• Redirect CORE light through mirrors.
• Balance laboratory coolant.
• Play a royal piano melody.
• Guide a chess knight across a board.
• Cross Cyber World’s timed traffic.
• Follow changing stage spotlights.
• Connect constellation threads.
• Balance forge weights.
• Solve a ring of flower petals.

Puzzle progress and first-completion rewards are saved separately for each player.

Hometown and Dark Worlds

Visit Hometown, with its school, library computer room, home, store and cafe.

Enter Dark Worlds through three different locations:

• School closet: begin your journey to Castle Town.
• Library computer room: enter Cyber World after completing King.
• Television: reach TV World after completing Queen.

Explore Card Castle, Cyber Streets, Queen’s Arcade, the Green Room, TV Studio, a silent sanctuary, an old forge and the Golden Garden.

The Underground and Dark World routes progress independently, letting you begin in either the Ruins or Castle Town. Use your journal to travel, check objectives and find nearby puzzles.

Undertale-Style Heart Battles

Boss encounters can switch into a soul arena where WASD or the arrow keys control your heart.

Each soul changes how you survive:

• Cyan: avoid recorded knife paths.
• Orange: keep moving through dangerous attack beats.
• Blue: handle gravity and jumping.
• Purple: move between three silk lanes.
• Green: turn a directional shield.
• Yellow: shoot a moving target with Space.

Survive cleanly to help earn MERCY, or press Escape to flee back to SAVE. Omega Flowey can cycle through all six soul mechanics.

Playable Characters

The UNDERTALE cast includes:

Chara, Sans, Asgore, Undyne, Papyrus, Toriel, Muffet, Mettaton NEO/EX, Napstablook, Asriel, Omega Flowey, Mad Dummy and Mad Mew Mew.

The dogs are playable too:

Doggo, Lesser Dog, Dogamy, Dogaressa, Greater Dog and Annoying Dog.

Explore the strange powers of the True Lab Amalgamates:

Endogeny, Memoryhead, Reaper Bird, Lemon Bread and Snowdrake’s Mother.

The DELTARUNE-inspired roster includes:

King, Jevil, Queen, GIGA Queen, Spamton NEO, Tenna, Roaring Knight, Titan, Hammer of Justice/Gerson, Shadow Mantle Holder, Pink and Flowery.

Their ability kits use different mechanics, including puppet strings, charged shots, boxing counters, TV portals, sword tunnels, shadow traps, ghost separation and companion-flower powers.

Character Transformations

Several characters change after their first defeat:

• Sans receives one extra life. His abilities unlock in his fragile 1 HP second life, with a purple aura and shifting eye colours.
• Undyne becomes Undyne the Undying.
• Asriel awakens a winged second form with stronger abilities.
• Flowery becomes Rainbow Flowery, doubling his movement speed and unlocking companion-flower abilities.
• Mettaton NEO transforms into Mettaton EX, unlocking five abilities through this mod’s custom progression.

Chara automatically converts iron swords into the Real Knife, dealing five times their damage at half their reach. Her heart changes colour with her active soul ability:

• Red: increased movement speed.
• Blue: higher jumps and softened falls.
• Purple: large teleportation lanes that respect solid obstacles.

Giant Omega Flowey

Become a towering TV-and-plant monster with 140 HP, moving jaws, arms and roots.

Unleash a charged TV Death Ray, thorn vines, bombs and flames, then draw on six different human-soul powers:

• Patience — Suspended Knives: record positions before knives cut across marked paths.
• Bravery — Boxing Ring: punish enemies who stand still during attack beats.
• Integrity — Gravity Ballet: drop ballet shoes onto warned positions, lift enemies and create landing pulses.
• Perseverance — Notebook Rails: send moving book rails across the battlefield.
• Kindness — Pan-Parry Kitchen: heal, parry frontal attacks and turn intercepted arrows into healing and splash effects.
• Justice — Six-Chamber Lock On: acquire targets before firing individually aimed shots. Solid cover breaks their locks.

Six-Soul Finale releases all six mechanics in sequence.

Flowery and Jarona-999

Flowery has a separate humanoid design and ability kit from Omega Flowey. Combine Jarona, Prism Blow, Glue and companion-flower powers, then unleash Jarona-999.

Jarona-999 creates a rapid blue barrage with afterimages and floating damage numbers:

• Requires an enemy within 2 blocks and a clear line of sight.
• Attempts 24 hits of 999 raw damage.
• Enemies can escape its range or take cover.
• Has a 30-second cooldown.
• Each eligible target has a 50% chance per cast to gain permanent immunity to Jarona-999, displayed as 000.

This immunity applies to Jarona-999 from any Flowery caster in the same world and persists through death, character changes, reconnects and world restarts.

An Entrance for Every Character

Every character has an entrance with full-body animation, temporary props, particles and sound.

Asgore raises his trident and smashes the SPARE button into separate halves and golden fragments.

Undyne leaps from a Waterfall cliff with her spear pointing down, lands in a water shockwave and rises into her guard.

Flowery falls onto a temporary cosmetic Ralsei and squashes him flat like a pancake.

Sans takes a sip of ketchup, Papyrus presents spaghetti, Toriel offers pie, Jevil springs from a playing-card box and Spamton NEO descends on green strings.

Omega Flowey assembles from roots, TV static and six orbiting souls.

Use /entrance to replay your intro and F5 to watch in third person. Combat interrupts the animation, and replaying it preserves your health, lives and ability progress.

Allies and Cooperative Attacks

Teamwork requires an accepted invitation:

1. Type /ally invite PlayerName.
2. Your friend types /ally accept YourName.
3. Join their boss encounter with /boss join AllyName, or prepare a cooperative attack.

Matching characters do not automatically make players allies.

Three character pairs have their own team attacks:

• Sans + Papyrus: a steered bone labyrinth and aimed overhead Gaster Blasters.
• Toriel + Asgore: a divided fire court followed by a shared heal.
• Chara + Asriel: a recorded route followed by a large moving star.

Both players need team charge. Request an attack with /teamattack AllyName, then have your ally use /teamattack accept YourName.

Either player can end the alliance with /ally remove PlayerName.

Getting Started

1. Craft a Soul Compass using a compass, an amethyst shard, an ender pearl and two gold ingots.
2. Right-click it to enter the Ruins and collect your starter supplies.
3. Challenge or spare bosses to obtain transformation souls.
4. Use a soul after combat to learn its character permanently.
5. Choose an ability item in your hotbar and right-click to use it.
6. Use SAVE shrines and /journal to manage characters, travel and follow your objectives.

Operator commands such as /sans, /chara, /jevil, /flowery and /omegaflowey remain available for creative setup and administration.

Installation

Requires Minecraft Java Edition, Fabric Loader, Fabric API and a compatible Java runtime. Check the selected download for its supported Minecraft release and dependencies.

Place Undertale Powers and Fabric API in your Fabric installation’s mods folder. For multiplayer, install matching mod files on the server and every client.

Credits

An unofficial fan mod featuring original mod artwork and custom Minecraft gameplay adaptations.

UNDERTALE and DELTARUNE were created by Toby Fox. Omega Flowey battle