DP077, 78 to air as one-hour special
The titles of DP077 and DP078, which will air as a one-hour special May 8, have been revealed. みんなライバル！ミクリカップ!! Everyone's a Rival! Mikuri Cup!! and 激闘!！それぞれのバトル!! Fierce Fighting! Respective Battles!! will be more episodes of Diamond & Pearl to feature Haruka, who is visiting from Johto.
In DP077, Nozomi appears at the Lake Resort with a newly-caught Keikouo, and Hikari begins to get nervous. Meanwhile, Satoshi and Haruka enter the Mikuri Cup with Buoysel and Kameil (which evolved in Johto).
In DP078, Satoshi and Pikachu are walking next to the lake when a glowing creature emerges from the water. It disappears when they try to approach it, so they return to the hotel and tell their friends of the lake's legend. The next day, the second round of the Mikuri Cup begins.