The Battle Era

The Battle Era is an ongoing period in the World Wrestling Entertainment (WWE) and the Total Nonstop Action Wrestling (TNA) that begun at TNA's premier pay-per-view event Bound for Glory in October 2014 when three WWE wrestlers (James Harrison, Roman Reigns & Dean Ambrose) entered the ring following Team 3D's match and attacked the wrestlers in-ring.
Almost every week WWE wrestlers turned up at TNA events attacking their wrestlers until Lockdown 2015 when Harrison, Reigns, Ambrose, Seth Rollins, Brock Lesnar and John Cena turned up promptly invading TNA.
Payback (2015) became an attempt for TNA wrestlers to get their paback against WWE wrestlers. This was a plan drawn up by WWE executive Vince McMahon to help TNA to grow and have stronger links with the WWE.