How to Solo Hell Castle with Ivy in Coop TD: Together

To clear Hell Castle solo using Ivy in Coop TD: Together, place your single Ivy tower near central track intersections, prioritize upgrading her attack speed over raw damage, and equip gems that scale critical hits. Because a solo strategy relies entirely on one primary damage source, keeping Ivy firing continuously without gold stockpiling is required to keep pace with enemy waves.

Gem Loadout Priorities

Your gem selection creates the multiplicative damage necessary for a single tower to keep up with late-stage enemy health pools. Focus your gem loadout on the following bonuses:

• Critical Damage Multiplier: Turns Ivy's high-frequency hits into heavy damage against high-health targets and bosses.
• Attack Speed Buffs: Increases attack frequency, directly driving how often critical hits trigger.
• Splash Damage or Piercing: Provides basic area control so smaller enemy clusters do not overwhelm Ivy's single-target focus.

Firing Position and Upgrade Order

Maximizing Ivy's line of sight is essential when running no secondary damage towers.

1. Place Ivy at central choke points: Position the tower where enemy paths converge or wrap around central loops. This minimizes downtime while enemies move through her range. Avoid corners or track ends, as these locations leave no buffer time if an enemy survives a burst.
2. Upgrade attack speed tiers first: Allocate early gold strictly to Ivy's speed tiers. Faster attack rates build the baseline hits required for consistent critical damage.
3. Reinvest gold immediately: Do not hold onto gold. Upgrade Ivy the moment you reach each cost threshold to keep up with scaling enemy health pools.
4. Use stall units only when necessary: If damage lags behind an incoming wave, invest temporarily in a slow or stall unit only to buy Ivy extra firing time, then resume focusing resources on Ivy.

Late-Game Target Management

During later waves, sudden spikes in enemy density and movement speed can breach defenses if target priority is left on default settings.

When major wave bosses appear, switch targeting to prioritize high-health targets manually. Focusing direct attacks on bosses allows Ivy's single-target critical damage to burst them down before they cross the finish line, while splash or piercing gems manage lower-tier units in the background. If a run fails at a specific wave tier, adjust your early spending speed on subsequent attempts so Ivy hits her next upgrade rank before that wave spawns.