Third Impact appears to be two entities. The first being a giant red glowing moon-like object. The second entity is an colossal white humanoid with with beady red eyes and large white antlers resembling ROBLOX user 123jl123. They also bear six wings on their back, three on each side. The upper torso of the entity is all a player can see, but their body extends beyond the map, making it the largest killer by far.
Upon the start of the round, the timer is frozen at 117 seconds and a large red moon will ascend out from the side of the map and cause a map-wide shockwave, the floor will then turn white, and "Third Impact" will appear holding the sun around their hands and grow 6 wings. Both entities remain in this position for the duration of the round. This sequence lasts around 55 seconds.
The timer will then extend to 160 and the attacks will begin to commence. The entity will then send out a myriad of bullet hell-like towards players. There are five different attacks the killer can send out:
- Red Beams: Third Impact will shoot multiple red lines through the ground that instantly kill if the player is caught in them.
- Green Crosses: Third Impact will shoot green crosses then a couple seconds later a green circle will rotate around the cross. When caught in the green ring the player will take medium damage. This attack will repeat two more times then dissipate.
- White Crosses: Extremely large bright white crosses will appear on the ground, creating a large red circle radius every once in a while. Getting caught within this circle will result in a player instantly dying and having their body parts dragged upwards into the sky.
- Black Hole: An area will be marked with a large red circle then a black hole will appear above it, sucking anything under it killing instantly.
- Angels: At 45 seconds into the round, angels will fall from the sky and target any player still alive. Once these angels make contact with a player, they will snap their neck and explode; turning them into an orange liquid.
- None of Third Impact's attacks bypass the Blue Relic.
- Third Impact will attack and kill ally NPCs.
- Third Impact is the largest killer in the entire game, being even bigger then Yama and Joel.
- Third Impacts model includes a lower half, which ends up being larger than the upper half that is seen by players.
- The cross-like attacks are in reference to the Crosses that appear in The End of Evangelion.
- Third Impact shares one of the same themes as A Beautiful Last Day.