who invade the celeron?

Answer 1

Intel.

"Since its launch, in April, 1998, Intel Celeron processor has been going through some changes. The name Celeron is used by Intel to denominate its low cost line of processors. In fact, Celeron is an economic version of Intel top processors. In other words, Celeron is a simplified version of Pentium II, Pentium III or Pentium 4, with some of its features being reduced or removed."

source:
http://www.dvhardware.net/article6722.html

regards,
Philip T