My Lands: Black Gem Hunting

When you hover your mouse over the vault, in the build menu, it says artefact, instead of artifact.

In Britain, the preferred form given in dictionaries is artefact, though the other often appears as an alternative. The Oxford Dictionary for Writers and Editors firmly suggests spelling it with an e, as does Bill Bryson in The Penguin Dictionary for Writers and Editors. However, the style guide of The Economist, with a large international circulation, suggests using artifact, since it is acceptable, it says, both to American and British readers. Americans prefer the i form by a large majority, but not exclusively so — newspaper practice seems to vary considerably, some insisting on the i form, others being more relaxed about it.

source: http://www.worldwidewords.org/qa/qa-art1.htm

molpx wrote:In Britain, the preferred form given in dictionaries is artefact, though the other often appears as an alternative. The Oxford Dictionary for Writers and Editors firmly suggests spelling it with an e, as does Bill Bryson in The Penguin Dictionary for Writers and Editors. However, the style guide of The Economist, with a large international circulation, suggests using artifact, since it is acceptable, it says, both to American and British readers. Americans prefer the i form by a large majority, but not exclusively so — newspaper practice seems to vary considerably, some insisting on the i form, others being more relaxed about it.

source: http://www.worldwidewords.org/qa/qa-art1.htm

Good answer!