In the Chimera Ant arc of Hunter x Hunter,
Netero and the Chimera King Meruem have a showdown, which leads to Netero's death, and later on, Meruem. The fight was pretty one-sided, considering the final state of Meruem compared to Netero, but it was to expect considering the former events.
We learn later that there are powerful adventurers out there (the Zodiacs), that have a seemingly tremendous amount of power.
My question is: why didn't Netero call them for help? He knew the enemy had a tremendous power, and he may have avoided what happened to him if he was helped during the mission (not even the showdown). So why did he call only those who are part of the mission in the Chimera Ant Arc? This could have been way less dangerous for them to have more firepower and capabilities.