Deltarune is Toby Fox's followup to Undertale, released in episodic chapters starting in 2018. It blends a fixed party RPG with bullet hell dodging in battle, and your choice to fight or spare shapes the tone of each encounter.
Boss fights are where Deltarune tests everything you've learned. This guide covers strategies for bosses across all areas, organized by progression order. For general combat techniques, see our combat guide.
Boss Areas in Progression Order
Hometown Bosses
Recommended level: Story hub Recommended build: Susie the reckless bruiser with Susie's axes
Strategy
The first bosses teach core combat mechanics. Defending means steering a heart through bullet patterns, so dodging skill protects the whole party each turn.
- Don't rush.
- Use Bullet dodging battles to create safe windows.
- Susie's axes is enough to handle everything here.
Field of Hopes and Dreams Bosses
Recommended level: Chapter 1 Recommended build: Susie the reckless bruiser with Susie's axes
Strategy
Early game bosses test your understanding of ACT and mercy system.
- ACT and mercy system is critical for these fights.
- Farm Susie's axes upgrades if you're struggling.
- Consider switching to Susie the reckless bruiser if your current setup isn't working.
Cyber World Bosses
Recommended level: Chapter 2 Recommended build: Kris the silent vessel with Kris's various swords
Strategy
Mid-game bosses are the major skill check.
- You need both Bullet dodging battles and Tension Point magic mastery.
- Kris's various swords makes a significant difference.
- See our combat guide for advanced techniques.
Card Kingdom Bosses
Recommended level: Chapter 1 Recommended build: Kris the silent vessel with Kris's various swords
Strategy
Late-game bosses are serious challenges.
- Make sure your build is fully optimized.
- Kris's various swords at max upgrade is recommended.
- Study each boss's attack patterns. Most have 2-3 phases.
The Dark Fountains Bosses
Recommended level: All chapters Recommended build: Kris the silent vessel with Kris's various swords
Strategy
Endgame bosses are the ultimate test.
- Top-tier build with best-in-slot gear is mandatory.
- Master every mechanic. See our combat guide.
- These fights reward patience and pattern recognition above all else.
General Boss Tips
- Learn before you fight: Spend your first attempt observing attack patterns.
- Match your build: Some bosses favor certain builds over others.
- Upgrade your equipment: A max-upgraded Kris's various swords trivializes fights that seem impossible with weaker gear.
- Use Bullet dodging battles: The core combat mechanic is your best defensive tool in every boss fight.
- Check the walkthrough: Our walkthrough tells you when you're ready for each boss.
Similar Games
If you enjoy Deltarune, check out these related guides:
- Elden Ring Boss Guide: rpg game with similar mechanics
- Baldur's Gate 3 Boss Guide: rpg game with similar mechanics
- Cyberpunk 2077 Boss Guide: rpg game with similar mechanics
