Merge a Nuke Spawn Tier should be prioritized when your base produces pieces that are too weak for the next goal. If pieces arrive slowly or crowd the board, spawn speed or capacity may be the better first fix.
What Spawn Tier solves
Merge a Nuke Spawn Tier matters when your merge chain starts too low. Better starting pieces can shorten the path to useful nukes and reduce repetitive early merges. This is especially helpful when your next goal requires higher-tier pieces.
What Spawn Tier does not solve
Spawn tier does not fix every problem. If pieces appear too slowly, spawn speed is the bottleneck. If the board fills before you can work, max spawn or Auto Merge may matter. If raids interrupt progress, defense may be more important.
Decision rule
Choose Merge a Nuke Spawn Tier when the issue is quality. Choose spawn speed when the issue is quantity. Choose capacity when the issue is space. Good upgrade planning starts by naming the bottleneck instead of buying the next shiny button.
Verification note
Exact tier prices and unlock values should be verified in game. This page explains the decision model and avoids publishing untested cost tables.