What the bar is telling you
Troops are shown as current, maximum, and gain per second. Gold is a stock plus a gain per second. If the maximum is the thing holding you back, you need the building that raises cap. AllThingsHow says that building is the city, and one article gives +25,000 troop capacity. That plus figure is a single publisher. TheGamesEdge agrees you build cities and factories first, without the 25,000.
Prices seen on one HUD
Historical RobloMine HUD, single source: city 500K, port 500K, factory 500K, defense 150K, silo 1.5M, SAM 1M, warship 750K, and nuclear buttons 750K / 5M / 25M. These are one frame’s labels, not a current universal price list. Reviewed 27 October 2026.
AllThingsHow’s separate price table lists a silo at 1M and SAM at 1.5M–3M; its city and factory tiers range from 125K to 1M. The silo and SAM figures differ from the historical HUD. Upgrade, mode and recording-date context is not fully established, so we preserve both records without selecting or averaging a current price. Checked 27 October 2026.
Growing the army
Troop gain per second is visible. Spending gold on factories is the income side; spending it on cities is the cap side. Sending troops does not increase income. It spends the stock the bar just showed you. Use the troop calculator if you want to preview a percent send. It does not invent a gold formula.
Source review: 27 October 2026. This page summarizes the linked public record; source-specific limits and historical observations are identified below.