You can play any game which supports local multiplayer lan by creating a hotspot and pointing IP address of each other computer on each one. Alternatively you can create a WiFi hostspot by your Windows 8.1 tablet too you just need to download and run a program called 'MyPublicWiFi' or through command prompt.I dont think any Modern game sports a lan mode but you can play desktop games like Halo, MTA:SA, Counter Strike etc.