Castle Busters: How to Use Leif and Sir Rally

To maximize siege damage in Castle Busters, deploy Leif first to destabilize the upper levels of an enemy fortress, then follow up with Sir Rally to destroy the ground foundation. This two-unit sequence bypasses frontal walls, shifts the base's center of gravity, and forces a structural collapse faster than relying on linear projectile units.

Unit Capabilities and Roles

Leif and Sir Rally serve complementary functions during an assault. Leif bypasses outer barriers from above, while Sir Rally delivers heavy melee demolition to the base.

Unit	Attack Trajectory	Primary Target	Main Risk or Limitation	Strategic Role
Leif	High-angle steep arc	Upper tiers & internal support beams	Slower projectile travel time requires lead aiming	Shifts base weight and creates upper structural soft spots
Sir Rally	Direct ground-level	Primary base foundation blocks	Poor mobility; easily blocked by lower wall debris	Collapses weakened structures from the bottom up

Execution Sequence for Castle Collapses

Targeting the physics of a castle layout requires executing your unit deployments in strict order:

Clear pathing obstacles: Deploy secondary units to eliminate low outer wall segments or debris blocking access to the enemy base's foundation.
Launch Leif's high-arc barrage: Aim Leif's projectiles at the less-dense upper blocks or internal support beams. This bypasses low defensive barriers and causes higher tiers to tilt or shift.
Identify structural instability: Watch for blocks flickering or leaning. Note the direction the base is tilting once upper supports fail.
Deploy Sir Rally on the foundation: Send Sir Rally directly to the base foundation blocks on the side opposite the tilt. Removing foundation support while the structure is unbalanced triggers a rapid collapse.

Timing and Deployment Safeguards

Account for Leif's travel time: High-arc projectiles take longer to reach their target than linear artillery. Wait to see where the castle shifts before launching follow-up shots to avoid firing into empty space.
Do not rush Sir Rally early: Deploying Sir Rally before clearing intermediate wall segments causes him to waste high-impact strikes on non-essential outer blocks.
Adapt to the lean: If an enemy structure leans significantly after Leif's initial hits but fails to fall, prioritize Sir Rally's attack on the elevated side of the tilt to finish the collapse efficiently.

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Emily Johnson

Emily writes practical mobile strategy guides with a focus on resource planning, base progression, and the early decisions that shape a long-term account.