"extra conditions" is a correct and usable phrase in written English.
You can use it to refer to additional terms or rules that must be fulfilled in order for something to occur. For example, "The landlord added extra conditions to the lease agreement before we could sign it."
But in these cases there are extra conditions.
When you accomplish your mission, the next level adds extra conditions and occasional targets.
Mr. Trantino said the extra conditions showed that "the parole board continues to be vindictive and politically motivated".
If new and extra conditions are becoming accepted so readily within psychiatric circles, shouldn't we at the very least explore this trend?
A conservative ally of the chancellor demanded extra conditions be put on the bailout, including sending a European commissioner to oversee spending cuts and accounting.
For, example, you can create your own contracts simply by playing through existing missions and tagging new targets for elimination, then adding extra conditions.
The much-ballyhooed agreement that rescue funds could buy embattled countries' bonds without onerous extra conditions was just a political promise to do something already allowed.
Their designers saw that CCTs had boosted household incomes, and asked whether extra conditions, such as mandatory school attendance, were necessary.
Turkey is complaining that the EU does not take it seriously as a candidate, and is always trying to slip in extra conditions for membership.
The land court president, Carmel MacDonald, recommended the state government approve the mine but with extra conditions around monitoring the impact on waterways and a local threatened species, the black-throated finch.
Jeremy Hunt's decision to approve News Corp's deal to buy the satellite broadcaster, with some extra conditions attached, will consolidate the media mogul's power in the UK at a time when one part of his empire is the subject of a police investigation.
