Game economy design is where the most interesting ethics in game development live. Every decision about what costs real money, what can be earned through play, how currencies interact, and where artificial scarcity is introduced — all of it is a statement about what you believe players are there for and how much you respect their time and their wallets.
This is Dev Diary #4. We have spent the previous three entries covering our technical architecture, the Labyrinth of Minds, and the Mystical Sanctum. This one is about money. Specifically: how we designed a three-currency economy for Avalon, why we chose a genuinely free-to-play model, how we built a Daily Deals system that creates engagement without exploitation, and what our anti-whale protections look like in practice.
We are going to be unusually transparent here, because we think the browser RPG space has a significant trust deficit with players and we would rather be part of the solution.
Why Three Currencies?
Avalon uses three currencies: Avalon Coins, Portal Gems, and Knowledge Crystals. This was a deliberate design decision that took longer to justify than almost anything else in the game.
Single-currency economies are simple but create a direct mapping between real money and gameplay value, which is a design problem when you want some things to be purchasable only through play. Two-currency economies (one earned, one premium) are the industry standard, for good reason — they are understood by players, they are easy to implement, and they give you a clean separation between free and premium content. We added a third currency because Avalon is a companion to a fiction website, and we wanted a currency that was earned through the fiction itself.
Avalon Coins
Avalon Coins are the base currency. You earn them by playing: completing quests, winning combat, exploring realms, logging in daily. They can purchase most in-game items — potions, equipment upgrades, NPC gifts, and a rotating selection of cosmetics in the standard shop. Coins cannot be purchased with real money. Full stop.
This matters. In many F2P games, the premium currency can be used to purchase the same things as the free currency, making the free currency feel like a degraded version of something you could have if you paid. We avoided this by giving Coins their own exclusive catalogue. There are things you can only get with Coins, things you can only get with Gems, and things you can only get with Crystals. No currency is the master currency.
Portal Gems
Portal Gems are the premium currency. They can be purchased with real money through the Premium Shop, or earned at a slow daily drip through login rewards (five Gems per day, which takes approximately two months of daily logins to afford the cheapest premium cosmetic). Gems purchase cosmetic items only — avatar borders, realm visual themes, title styles, and special dialogue animations. They cannot purchase gameplay advantages, equipment stat improvements, or quest unlocks.
We use the term “cosmetics only” precisely. No premium item affects combat outcomes, quest availability, NPC relationships, or story access. A player who has spent money on Portal Gems and a player who has never spent a penny have identical access to all gameplay content. This was a non-negotiable design principle from day one.
Knowledge Crystals
Knowledge Crystals are earned by engaging with Portal Avalon’s fiction. Reading a story to completion awards Crystals. Completing lore quests with the Archivist NPC awards Crystals. Writing a review or comment on a story awards a smaller Crystal bonus. Crystals can only be spent on cosmetics that are thematically tied to the fiction — avatar frames named after story characters, realm themes that match the visual language of specific story categories.
The function of Knowledge Crystals is to create a tangible connection between the game and the fiction. Players who engage with both worlds are rewarded in both. It also gives Portal Avalon’s story readers a reason to visit the game, and game players a reason to read the fiction. The conversion rate in testing was better than we expected: approximately 40% of players who earned Crystals through reading returned to earn more.
The Decision to Go Free to Play
The alternative was a subscription model or a one-time purchase gate. We considered both seriously.
A subscription model — say, £3.99 per month for full access — would have provided predictable revenue and removed most of the ethical complexity of F2P design. It would also have significantly reduced our player base. Avalon is a companion to a fiction site, not a standalone game product. Players arrive from stories, from blog posts, from search. Most of them have no prior relationship with the game. Asking them to pay before they know whether they enjoy the experience is a significant barrier.
A one-time purchase gate has similar problems. The game needs to demonstrate its value before it asks for payment, and the value of a browser RPG connected to a fiction ecosystem is not immediately obvious until you have spent time in both.
F2P, done ethically, removes the barrier to entry entirely and creates the possibility of a relationship before it asks for a financial commitment. The ethical burden is then on the design of the monetisation layer — which is where the real work is.
The Premium Shop: What We Sell and Why
The Premium Shop is accessible from the game HUD and updated monthly with new cosmetics. It has four categories: Avatar Borders (decorative frames around the player’s avatar icon), Realm Themes (alternate visual palettes for each realm, replacing the default deep violet and gold), Title Styles (custom fonts and colour treatments for the player’s display name), and Dialogue Animations (optional animated effects in NPC conversation windows).
Each category has a permanent collection and a seasonal collection. Permanent items are always available. Seasonal items cycle in and out on a monthly basis, but we have committed publicly — and will enforce through our changelog — to returning seasonal items to the shop within twelve months. We do not create items that permanently disappear. The fiction of scarcity in cosmetic shops is one of the most corrosive practices in F2P gaming, and we refuse to use it.
Prices are set at levels that reflect the labour involved. Avatar Borders cost between 50 and 200 Portal Gems. Realm Themes, which require the most design work, cost between 150 and 400 Portal Gems. The cheapest pack of Portal Gems purchasable with real money provides 200 Gems for £1.99. A player can meaningfully participate in the Premium Shop for less than £5 per year.
Daily Deals and Ethical FOMO
FOMO — Fear Of Missing Out — is a real psychological mechanism and a standard tool in F2P game design. Daily rotating shops, limited-time offers, countdown timers: all of these work by exploiting the psychological discomfort of potential loss. They also work by creating daily engagement, which matters for retention metrics.
We decided to use a Daily Deals system, and to use it in a way that acknowledges what it is while removing its most harmful elements.
Each day, three cosmetic items are available at a 30% discount. One of those three is always purchasable with Avalon Coins rather than Portal Gems. The rotation refreshes at midnight UTC. Items are not removed from the game when their Daily Deal window closes — they return to the permanent shop at full price. The Daily Deal creates a financial incentive to engage daily, but it does not create a content incentive. Missing a Daily Deal does not mean missing content; it means paying slightly more for the same item at a later date.
We also do not use countdown timers on Daily Deals. Timers are effective precisely because they create urgency that bypasses deliberate decision-making. We want players to decide to purchase, not to feel that they are racing against a clock. The deal refreshes each day. You know when it refreshes. There is no need for a countdown.
Spending Caps and Anti-Whale Protections
The term “whale” in game economy design refers to a small percentage of players who spend disproportionately large amounts of money. In some F2P games, a tiny fraction of the player base — sometimes under 1% — generates the majority of revenue, because the game is designed to extract maximum spending from those most susceptible to spending loops.
We implemented a hard monthly spending cap of £25 per account. Once a player has spent £25 in a calendar month, the Premium Shop displays a ‘Monthly cap reached’ message and disables all purchase buttons until the following month. The cap is enforced server-side. It cannot be bypassed by creating additional accounts linked to the same payment method (Stripe’s fraud detection handles most of this, and we have additional checks).
The cap also has a practical effect on our revenue model: it makes our revenue more predictable and more evenly distributed across our player base, which is a healthier financial structure than one dependent on a small number of high-spend accounts.
Future Stripe Integration
At the time of writing, the Premium Shop is in a pre-launch state with simulated purchases. Stripe integration is planned for Q3 2026. We have chosen Stripe because of its robust fraud detection, its support for subscription and one-time purchase flows, and its strong compliance infrastructure for UK and EU payment regulations. We will use Stripe’s built-in spending controls as a secondary enforcement layer beneath our own cap logic.
When Stripe goes live, we will also implement Stripe’s card decline grace period — which pauses rather than immediately cancels when a payment method fails — to avoid penalising players for payment failures that are their bank’s error rather than their own.
What We Got Wrong (So Far)
No dev diary should be entirely self-congratulatory. A few things we got wrong in early design and corrected.
Our first currency design had Portal Gems earnable at a rate that was practically indistinguishable from zero for non-paying players. The daily drip of five Gems was added after internal testing made clear that a currency that can technically be earned but practically cannot be is dishonest. We raised the drip rate and added the daily login bonus specifically to ensure that a patient free player can genuinely participate in the premium economy over time.
We also initially planned to have one cosmetic category that offered a minor gameplay convenience — a reduced cooldown on one rarely-used ability. We removed it. The line between cosmetic and functional is one we will not blur, even for something as minor as a cooldown reduction. Once that line moves, it tends to keep moving.
Dev Diary #5 will cover quest design across all realms. Until then, the game is free, the Sanctum is waiting, and Merchant Thorn has new stock in the Daily Deals.