An Unlockable (Achivements/Secret Hidden Levels) Object

An Unlockable object is in the following format

<unlockable>
  <line>
   <col>Unlockable Title</col>
   <col>Instructions to Unlock</col>
  </line>
</unlockable>

the <unlockable> object may have between 0 and unlimited <line> elements

A item that has the unlockables ‘NO-ONE LEFT BEHIND’ and ‘HELPING HAND’

<unlockable>
  <line>
   <col>NO-ONE LEFT BEHIND</col>
   <col>Beat a campaign with all 4 Survivors.</col>
  </line>
  <line>
   <col>HELPING HAND</col>
   <col>Revive 50 incapacitated Survivors.</col>
  </line>
</unlockable>