This is proof that you've equipped items that activate a Stack bonus skill. You can get Stack bonuses by equipping more than one copy of the same skill at once. The more copies of that skill you equip, the cooler your Stack bonus will be!
This is proof that you've equipped items that activate an Elemental Union bonus skill. Basic skills all correspond to one of five different elements. Equip skills of the same element that line up directly adjacent to each other, and you'll form an Elemental Union based on how many skills are in the line. Check it out on the skill sheet!
Purchased one Attribute.
Level 5 reached.
Killed 100 zombies.
Killed 1,000 zombies.
Stranded survivor saved.
Completed the prologue.
Complete a single street crime case.
Clear a case finding every clue as an LAPD Detective or Investigator.