Invincible Battle Power System is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

Rebirth against the odds, unlocking invincible battle power! A loser male protagonist, reborn against all odds, obtains the system. Just by killing monsters, he can upgrade and increase his battle power! And he can also have unlimited equipments! “I won’t tell you that the clothes I’m wearing are battle power equipment! A single pair of underwear alone can increase my combat power by a thousand! What? Why do you think my strength is increasing so fast? I tell you, I can increase my combat power by stepping on an ant or destroying a cockroach!”