Operate every state without relying on one cue
Check keyboard and assistive focus order, readable labels, contrast, zoom, reduced motion, timing, error recovery, and non-color status signals. Confirm and cancel need distinct names and positions, while delivery must be announced and visible in its normal game context.
Run a price-comprehension check
Give a new player the offer without explanation and ask them to name the selected item, full Koin amount, available balance, expected balance afterward, quantity or duration, and ownership rule. Let them decline, then repeat with insufficient Koin and a successful choice. Review every place the value appears and remove crossed-out amounts, vague premium labels, unsupported real-currency comparisons, or urgency that distracts from the final cost. The wording on the preview, confirmation, success message, and owned view must describe the same thing. Reopen the game and verify that the balance and ownership shown to the player still match the one transaction they approved.
Keep price and balance together
Place the exact Koin amount beside the available Koin balance and show the expected remaining balance ahead of confirmation. For accessibility-first players, the experience must support readable labels, non-color cues, focus order, and reduced-motion review.
Explain duration and ownership
State whether the item is permanent, consumed on use, limited by quantity, or active for a fixed time. For accessibility-first players, the experience must support readable labels, non-color cues, focus order, and reduced-motion review.
Remove misleading price signals
Avoid fake urgency, crossed-out prices, unsupported currency comparisons, and labels that hide the final Koin amount. For accessibility-first players, the experience must support readable labels, non-color cues, focus order, and reduced-motion review.