Thank you for your reports and feedback! This patch fixes two bugs and improves milestone progression and the optional challenges.

• Fixed Brood genes not stacking correctly. Their reserves now combine as intended, providing 16 replacement swarm members per fully devoured prey when both genes are equipped.
  
• Fixed allied Artillery drones disappearing near screen edges while their shots remained visible. Drones and projectiles now use the same world view as the enemies.
  
• Reduced the final cell milestone from 100 million to 20 million and updated its achievement icons and localized descriptions. Existing achievement unlocks are preserved.
  
• Rebalanced the three optional challenges. Small Colony, Mixed Threats and Limited Resources now require 8, 20 and 10 fully devoured prey respectively, with revised Hunger budgets. Small Colony's 150-member limit applies from the start, and giant prey are limited to one smaller giant per attempt in the challenges that include them. Challenge completion now happens immediately when the goal is reached.
  

Prey still need to be fully devoured, and previously unlocked challenge colors are preserved. These challenge adjustments do not change the main campaign or the swarm's speed limits.