Double Impact (ダブルスライド Daburu Suraido, lit. "Double Slide") is a technique that appears in Kingdom Hearts 3D: Dream Drop Distance. It allows the user to perform a second charging attack after using Sonic Impact which sends enemies flying.
Mechanics
In Kingdom Hearts 3D: Dream Drop Distance, Double Impact is an movement command that is triggered by and pressing 
immediately after using Sonic Imapct.
Learning Double Impact
Kingdom Hearts 3D: Dream Drop Distance
- Sora learns Double Impact after retrieving the Sound Idea.