Are Pokémon Rumble World's microtransactions a shakedown?

Less than two months since the launch of its first free-to-play Pokémon game, Nintendo has today released another.

3DS dungeon crawler Pokémon Rumble World takes the simple gameplay of the Pokémon Rumble/Scramble spin-off series and makes it free to download.

But, like February's Pokémon Shuffle, it isn't free to play without limits.

The game uses a couple of currencies: the in-game coins that enemies emit upon their defeat, and the paid-for Poké Diamonds.

There's also a cooldown mechanic, which limits your progress through the game unless you wait (or pay).

Different in-game areas are reached by hot-air balloon, which must inflate between uses. As the game itself states:

"The hot-air balloon deflates after you use it. Some time must pass before it inflates again. If you use Poké Diamonds, you can get it inflated again right away.

"Hot-air balloons inflate quickly until you reach Adventurer Rank 5."

Up to Adventurer Rank 5 the hot-air balloon takes seconds to refill. But we've passed Rank 5 and this has only increased to a minute or so.

But the more expensive and powerful models necessary to reach the later, stronger Pokémon, take far longer. Top-of-the-line hot air balloons take you to the rare fairy and dark Pokémon zones and require five hours to reinflate, or three Poké Diamonds.

The final zone, which requires the 100 Poké Diamond-cost Origin Balloon, takes you to where Pokémon from the original Red and Blue games, including Mewtwo, appear. This balloon takes six hours to reinflate, or three more Poké Diamonds.

You also have the option to spend Poké Diamonds to continue without penalty should your Pokémon faint mid-level, or for other in-game items that affect gameplay.

Initially, players are limited to holding 30 Pokémon at any time, but this can be upgraded by paying two Poké Diamonds for a "Pokémon House".

So how much do Poké Diamonds cost? Here's a list, direct from the in-game shop:

Regular prices:

• 50 Poké Diamonds - £0.69
• 100 Poké Diamonds - £1.19
• 200 Poké Diamonds - £2.19
• 500 Poké Diamonds - £4.99
• 1000 Poké Diamonds - £8.99
• 1750 Poké Diamonds - £14.39

For a limited time:

• 50 Poké Diamonds - £0.49
• 200 Poké Diamonds - £1.59

Meanwhile, in-game coins can be spent on customisation options for your Mii character - new costumes and the like. At present there doesn't seem to be any way of exchanging coins for Poké Diamonds.

Our initial play session of around half an hour saw us gifted a generous amount of Poké Diamonds to start the game and go shopping for a few items. We were also gifted Diamonds by characters we had StreetPassed or had met via the internet.

"To help their progress, players will collect or buy Poké Diamonds, which can make their adventures more fun and help them on their mission to discover Toy Pokémon," Nintendo stated today.

"The game can be thoroughly played throughout at no cost or players have the option to buy items to help them quickly progress through the game."