Intrusion Coins are items given once players have maxed out any level with the Fever System, thus meaning a maximum of three coins per day. These coins allow players to intrude themselves in any Zombie Mode match past their last joinable waves (17 on Easy and 25 in Normal and Hard respectively). Players can jump in at any time during that period, even in the middle of the boss fight (both Normal and Hard difficulty), thus possible to end the round with 0 points and just collect boss tokens on a succesful boss defeat.