How do you get onix unova rpg for free?

To get Onix in Unova RPG for free, you can participate in special in-game events or promotions that may offer the Pokémon as a reward. Additionally, you can check trading forums within the game community where players may be willing to trade an Onix. Keep an eye on updates or announcements from the game's developers for any opportunities to acquire rare Pokémon without spending money.