B.A.P. (originally Anti-Police Brigade) or eventually BAP!!! They began as a quite normal punk band. Example (Torture no!):
But unlike most other groups, they truly evolved. Here at an early stage of their evolution (Bhopal, from Popular Beans and Cabbages - 1984):
Eventually they became the best that Basque music has ever produced (arguably, of course). So we got jewels like Inolaz ezin dut ahantzi (No way I can forget):
Or Ez duzu erahilko (You shall not kill):
Sadly, soon after these fantastic songs and the corresponding concerts, they dissolved. Some of the members recycled themselves into DUT (I have), a great band, no doubt, but it was not the same at all.