When playing Tideturner as a hidden card at a battlefield, can it target units at other locations (like base), or is it restricted to only units within that battlefield?

Ruling: Tideturner can target units at other locations (including base) even when played as a hidden card at a battlefield, because its ability explicitly restricts targeting to "a unit you control at another location," which makes the normal hidden card targeting restriction impossible to follow.

Nuances:

• The general rule is that hidden cards at a battlefield must target options within that battlefield
• However, when an ability explicitly restricts targeting in a way that makes this impossible, the ability's targeting restriction takes precedence
• Tideturner has errata that specifies "at another location" in its targeting text