Learn Turkish: Her gün bahçede saklambaç oynardık. - We used to play hide-and-seek in the garden every day.

It uses the aorist past tense, which is often called the habitual past. You take the verb root oyna- (to play), add the aorist suffix -r, the past tense suffix -dı, and the personal "we" ending -k. Together, -rdı- expresses an action that was a regular habit in the past, similar to "used to" or "would" in English.

Why is the aorist suffix just -r here, rather than -ar or -ır?

Because the verb root oyna- ends in a vowel. When a verb root ends in a vowel, the aorist suffix is always just -r. You only need to worry about choosing between the vowel forms (like -ar/-er or -ır/-ir) when the root ends in a consonant.

Why is there no case ending on saklambaç?

When talking about playing a game or a sport, Turkish uses the plain dictionary form of the noun right before the verb. So, "to play hide-and-seek" is simply saklambaç oynamak, with no accusative or dative endings required on the game itself.

Could I say oynuyorduk instead of oynardık in this sentence?