This morning he admitted importing 20kg of methamphetamine as well as 26kg and 50,000 pills of MDMA into Auckland, between August 2017 and November 2019.
He also admitted selling and possessing illegal drugs for supply, possessing materials for the manufacture of methamphetamine, and unlawfully possessing a military-style firearm.
Alarcon Ramos, who was supported by his wife, sister and pastor in court this morning, will be sentenced on August 18.
The drug syndicate is alleged to have imported over a tonne of methamphetamine, MDMA, cocaine and ephedrine into the country over three years.
At the time of the arrests, the police said the National Organised Crime Group and Customs had focused on a "key player" living offshore, who had since been arrested at an Italian border.
They said a 31-year-old New Zealand man living overseas had been concealing and sending drugs back to his associates via different countries.
The police executed search warrants at 11 properties in Auckland central, Henderson, Wairau Valley, West Harbour, Takanini, Waterview and Beach Haven.
They seized more than $1 million in cash as well as high end cars and firearms, including a military-style rifle.
National Organised Crime Group's Detective Inspector Paul Newman said the operation was a sophisticated, large-scale international drug syndicate.
"New Zealanders are using about 13kg of methamphetamine a week according to recent wastewater analysis, so a tonne of methamphetamine, or its precursor ephedrine, equates to more than a year's worth of national consumption," he said.
"By arresting and stopping this syndicate's key player, along with his alleged associates, it will go a long way to reducing the amount of this drug being imported into New Zealand, and preventing the harm it causes to our communities."