Reinforcements are called even if you're still alive.
Last standing during a Wave (once).
"Call the reinforcements! I... I've bumped my little toe!"
Crybaby is an unlockable active Ability. It allows the Trooper to deploy the Next Wave without dying first, but only if he's the last Trooper remaining in the current round. The ability can be triggered regardless of whether there are any extra teammates that can be deployed. If multiple troopers survive on the battlefield and they all have this skill, Crybaby will still be activated.
If the trooper is deployed alone (for example, if multiple Reverse Attacks or Spies reduce the deployment to 1, or the trooper enters in a vehicle that takes up the whole deployment capacity), Crybaby will trigger immediately in the first case and as soon as the trooper dismounts or blasts out of the vehicle in the latter (provided he survives the explosion).
This one is good for outnumbering the enemy, especially if some of the soldiers in the wave have the Survivor skill. It has a similar effect to Martyr, except it is slightly less likely to trigger since it requires the soldier to be the only survivor on the team.