An adult card game which lets players pretend to be cannabis-dealing kingpins is being sold at Toyworld Nelson.

In Grass, players use cards to mimic dealing cannabis, stealing from one another and protecting their "stash" to amass drug money. Individual cards include "Steal your neighbour's pot", "Catch a buzz" and "Lust conquers all".

"Like the real thing, it's easy to learn," say the tongue-in-cheek instructions. "We suggest that you begin gradually with Grass, till you get used to it."

At Toyworld, it hangs in the puzzles section next to decks of playing cards and games like Uno.

Grass is out of the reach of most little hands, but would stand out to any older children who could identify the distinctive cannabis leaf emblazoned on the packaging.

A saleswoman, who did not wish to be identified, said the game was never sold to customers under 18, although the store did not ask for identification.

Toyworld Nelson also sells other card and board games targeted at adults, and maintains a voluntary R13 rating on popular Magic: The Gathering cards.

"They don't rate [Grass], but it's never children who buy it. It's always adults," the saleswoman said.

"We don't promote selling [cannabis] or smoking it or anything. It's just a game."

She said the game had first been stocked by a previous store owner, and had been sold in Toyworld for at least nine years.

Customers regularly requested it and four units had been sold so far this year. There had been only three complaints overall.

Toyworld national buyer Repeka Haurua said the Nelson store was independently owned, so owner Lindsay Hicks could stock any product he wanted. Hicks was not willing to comment.

In response to a description of the product, Haurua said Grass was not a product Toyworld would support or encourage. She confirmed that the game was not stocked nationwide.

"It's not something I would ever promote and it's not something I would buy," she said.

"[Consuming cannabis] is a behaviour that we don't condone."

She said it was "terrible" that Nelson customers requested Grass, but commented that supplier Ventura Games was having no problem finding retailers to stock the game.

Sergeant Mal Drummond said the game sounded "unusual", but there was nothing illegal about it.

He was surprised that Grass was sold at Toyworld Nelson.

"If it's just promoting drug dealing, I can't see how it can be a positive game, but to 99 per cent of people who would use it, it's just a game."