Ultraman Tiga's statue was present on Earth. But in the case of Ultraman Trigger, his statue exists on Mars. Kengo will use the GUTS Hyper Key that had absorbed the statue's light.
Ultraman Trigger's new Kaiju Golba (basically the fused version of Tiga's Golza & Melba) is an Ancient Monster controlled by the Dark Giants. With his Flame Bullet, he will attack the Mars Colony.
Carmila has a 30 million years old grudge against Ultraman Trigger and she will attack him multiple times. She can also use a whip and summon staff which she can rotate to use as a fan.