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Infinite Castle Mode – UTD Guide (Floors, Checkpoints, Scaling, Efficient Farming)

Floor-based endurance ladder focused on checkpoints, scaling, and consistent clears.

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Table of contents

Infinite Castle Mode is UTD’s floor-based endurance ladder: instead of a single act or a continuous endless loop, you climb a castle one floor at a time, facing escalating pressure and periodic checkpoints. The “castle” format rewards two things at once:

  1. consistency (you must beat many floors in a row), and
  2. adaptation (each floor or bracket may shift enemy types, density, or boss patterns).

If Endless Mode teaches long-run scaling and Tournament teaches scoring efficiency, Infinite Castle teaches stability under repeated checks—your build must handle swarms, tanks, air threats, and bosses without collapsing when a floor spikes.

This guide explains how Infinite Castle typically works, how to plan floors/checkpoints, how to build reliable teams, and how to farm it efficiently.

Unlock & Entry Requirements

Infinite Castle is usually unlocked after meaningful Story progression and/or a minimum account level (patch-dependent). Higher castle floors often assume you have:

  • a strong carry with traits/relics,
  • at least one debuffer,
  • a control option,
  • and some coverage flexibility (AoE and/or anti-air).

Some versions gate higher floors behind:

  • clearing earlier floors,
  • completing a quest line,
  • or meeting unit level requirements.

Recommended readiness:

  • One main carry you can upgrade to a stable “online” state quickly.
  • One debuffer for tank/boss floors.
  • One AoE unit (or carry variant) for density floors.
  • One control option for fast floors and boss windows.

Infinite Castle punishes incomplete role coverage. You can’t “just brute force” a floor you don’t have the tools for.

Gameplay Rules & Loop

What Infinite Castle is

While exact implementations vary by patch, the castle format commonly includes:

  • A sequence of floors that must be cleared in order.
  • Floors grouped into brackets (example: every 5 or 10 floors) with a checkpoint or boss.
  • Scaling enemy HP/speed/density as you climb.
  • Rewards tied to floor milestones and sometimes repeatable farming of a bracket.

Some versions allow a “start from checkpoint” after you reach it once; others require full climbs.

The core loop

  1. Clear early floors efficiently with minimal spending.
  2. Establish a stable carry + support chain before the first checkpoint.
  3. Beat checkpoint bosses cleanly using debuffs and burst timing.
  4. Adapt for floor spikes (density floors, speed floors, air floors).
  5. Push to the next checkpoint, then decide whether to farm or keep climbing.

Infinite Castle is about repeatable floor performance, not one perfect wave.

Rewards

Infinite Castle rewards are often tied to milestones:

  • floor clear rewards,
  • checkpoint milestone bonuses,
  • currencies/materials that scale with progress.

Depending on patch, the mode may be a strong source of:

  • relic-related materials,
  • crafting or evolution resources,
  • limited tokens tied to the castle season.

Best for

  • Long-term progression milestones.
  • Farming stable checkpoint brackets once unlocked.
  • Testing a “balanced” roster under mixed threats.

Not ideal for

  • Short-session gem farming (Story is usually quicker).
  • Pure unit EXP grinding (Endless is often better per time once stable).

Difficulty & Scaling Notes

Castle difficulty scales in steps:

  • floors gradually become harder,
  • checkpoint bosses mark major jumps,
  • some floors act as “role checks” (air, AoE, control).

You will usually hit a “wall” when one of these fails:

  • your carry can’t kill tanks fast enough (need debuff or burst),
  • density overwhelms you (need AoE or better placement),
  • speed causes leaks (need control),
  • mixed threats expose coverage gaps.

Avoid assuming exact scaling multipliers unless verified. Treat unknown values as TBD and build around roles and breakpoints.

Strategy

Early Floors (Stabilize and Save)

Goal: clear early floors with minimal cost so you enter checkpoints strong.

  • Use one efficient early unit and upgrade it instead of spamming placements.
  • If economy units exist and the castle run length supports them, consider early economy. If the mode is short to checkpoint, economy may not repay.
  • Place your carry at a high-uptime position (corners/long straights).
  • Keep supports aligned with the kill zone—don’t spread auras across irrelevant lanes.

Early checklist

  • Stable clear without micro.
  • Carry placement chosen.
  • Money reserved for checkpoint preparation.

Checkpoint Preparation

Goal: make your carry and debuffs ready before the boss arrives.

  • Upgrade your carry to its first major breakpoint before the checkpoint boss.
  • Add debuffer uptime: if your debuff is down during the boss, your effective DPS collapses.
  • If the checkpoint includes adds, set up a cleanup AoE near the end path.

Mid Floors (Role Checks)

Goal: adapt to floor spikes without ruining your economy. Common floor spike types:

  • Density floor: many enemies → AoE clear, splash uptime, kill-zone engineering.
  • Tank floor: fewer but tanky → debuff uptime, single-target upgrades, burst timing.
  • Speed floor: fast enemies → control timing, increased coverage time.
  • Air floor: flying threats → anti-air coverage or hybrid units.

Decision rule

  • Leaks on fast waves → control.
  • Leaks on swarms → AoE clear.
  • Boss/tank stalls → debuff + carry upgrades.

Late Floors (When Scaling Outpaces You)

Goal: extend your wall and stabilize farming.

  • Add multipliers (buffer + debuffer) instead of adding low-impact DPS towers.
  • Optimize placement for time-on-target.
  • Keep a cash reserve for emergency upgrades on spike floors.
  • If your failure wave is consistent, treat it as a design problem: what role is missing?

Team Building

New Player Loadout (4 Slots)

A practical Infinite Castle lineup:

  1. Main Carry

    • Reliable uptime and stable scaling.

  2. Debuffer

    • Mandatory for tank/boss checkpoints.

  3. Coverage

    • AoE for density floors OR anti-air if the castle spawns flyers.

  4. Flex Utility

    • Control if speed floors are common,
    • Buffer if your carry is already strong,
    • Second coverage if mixed threats appear often.

Principle: carry + debuff + coverage + one utility.

Advanced Player Blueprint (6 Slots)

A stable “castle climb” framework:

  1. Main carry
  2. Secondary DPS (AoE or burst)
  3. Debuffer
  4. Buffer
  5. Control
  6. Flex tech slot (extra debuff, shield break, map-specific coverage)

In high floors, one buffer/debuffer combination can be worth multiple DPS units because the slot limit makes multipliers more valuable.

Trait & relic priorities (high-level)

  • Carries: damage/attack speed and uptime improvements.
  • Debuffers: cooldown/range for uptime.
  • Buffers: range/cooldown for coverage.
  • Control: cooldown/range to handle repeated speed spikes.

Common Mistakes and Fixes

  • Mistake: Treating every floor like the same wave

    • Fix: identify spike floors and design specifically for them.

  • Mistake: No debuffer

    • Fix: checkpoint bosses often require amplification more than another DPS tower.

  • Mistake: Overbuilding economy

    • Fix: economy is only good if it pays back before your first major checkpoint.

  • Mistake: Supports not covering the kill zone

    • Fix: move supports so buffs/debuffs apply where your carry actually fights.

  • Mistake: Pushing with low success rate

    • Fix: farm the highest checkpoint you can clear consistently; expected value improves.

Advanced Optimization Tips

  • Track your “wall floor” and record what kills you (tanks, swarms, speed, air).
  • Create two builds: one “density-first” and one “boss-first,” then swap by floor pattern.
  • In co-op castle variants, split roles: one player runs buffer/debuffer/control, the other runs carries and coverage.
  • Optimize your upgrade sequence to reach “carry online” earlier—this increases floor stability dramatically.

Calculator Shortcuts

  • Upgrade Planner: map the cheapest path to beat the next checkpoint boss.
  • DPS Calculator: compare carry choices and trait/relic swaps.
  • Mode Fit: model checkpoint boss HP with manual inputs and compare TTK.
  • Team Validator: verify coverage roles (AoE, anti-air, debuff, control).

FAQ

Q1: Should I farm checkpoints or always push higher?
Farm the highest checkpoint bracket you can clear consistently. Push only after your farm tier is stable.

Q2: Why do I lose on specific floors repeatedly?
That floor is a role check. Identify the failure type (speed, density, tank, air) and fix the missing role.

Q3: What matters more at high floors: another DPS or a buffer/debuffer?
Usually a buffer/debuffer. Multipliers improve your best damage and scale with slot limits.

Q4: Why does calculator DPS differ from castle runs?
Range downtime, targeting, spike floors, and imperfect buff/debuff uptime change real outcomes. Use calculators for comparisons and planning.