Blast has finally shown up. This time it is not a flashback or somebody thinking about him, this is literally blast for the first time ever in One Punch Man manga. Blast has been a mystery to fans ever since his mention in S Class meeting.

Blast appears suddenly in One Punch Man 139 when a mysterious black block starts talking to Saitama and the others. Blast then took the block and moved it somewhere. This is the first time that Saitama and Flashy Flash have met Blast. Flash than wants to test the strength of Blast first, but Blast easily avoids it and asks Flash to calm down.
What is Blast’s Power?
From what we see in Chapter 139, Blast have teleportation powers. He can teleport any object and himself as well. Blasts can also move other people to the surface. He brings Flash and Saitama to the surface, after they had been trapped for a long time.

Apart from that, Blast can also easily dodge Flash attacks. Seeing Flash’s reaction after Blast asked him to calm down, he looked completely shocked. Even so, Saitama didn’t react. So even though he is very strong, and maybe even stronger than Tatsumaki, Blast doesn’t seem to be on the level of Saitama huh.
Why Did Blast Disappeared?
This question has not been answered in the manga yet but from what information is available we can speculate that Blast is on a special mission.
Blast is collecting Black Boxes which are used to communicate with the god entity. In chapter 139, blast also said that he has a hobby of collecting these black boxes. God entity knew who Blast was.
So … could it be that Blast disappeared for a long time because he had some really important business? He was probably collecting blocks from all over the world, and was actually going to fight the threat of the god?