LOVE IT!!! Also, did you know you can play ONLINE in 2023??? Here's how... (Sorry for the LENGTHY tutorial...)
For games OTHER than Pokemon Gen 5 (works on any DS): Set a portable hotspot up using OPEN security (essential for the DS to connect with older games), then set a MAC Address filter (So only the DS can connect) and SSID broadcasting OFF (so nobody can find it without knowing the name). Once the hotspot is configured, go to the DS game (In this case, Mario Kart DS) and go to Nintendo WFC (or whatever the "online" option is), and tap "Nintendo WFC Settings". Once you're there, tap the ORANGE button to get your DS MAC Address, and put that into the hotspot. Once you've done that, go back to the WFC Setup menu, and tap the BLUE button, to set up a Wi-Fi connection. Tap an empty connection, and choose MANUAL setup. Then enter your hotspot SSID with NO WEP key, and the DNS. Set the Primary DNS to 164.132.44.106, and the Secondary DNS to 8.8.8.8. This will connect you to Wiimmfi (an alternate WFC server). Test, and if it says "Connection successful!", you're good!
For the Pokemon Gen 5 games (Requires DSi or 3DS family system): Go to the System Settings app, and scroll to the second page (DSi) or tap the Other Settings button (3DS) to find the Internet settings. Tap an EMPTY connection (on 3DS) or Advanced Setup, then an EMPTY connection (on DSi), and choose Automatic Setup. Then find your Wi-Fi SSID and set it up like normal. Then, when the connection is successful, go to the connection, and change the DNS. Set the Primary DNS to 164.132.44.106, and the Secondary DNS to 8.8.8.8. This will connect you to Wiimmfi (an alternate WFC server). Test, and if it says "Connection successful!", you're good!
Then you can play ONLINE just like you were able to before 2014!