Arkham Asylum Incident
When Ivy was freed from her cell in the Green Mile by Harley Quinn, she made the Botanical Gardens her lair.
Arkham City Incident
When Catwoman needed help breaking into Hugo Strange's Vault, she headed to Ivy's Lair, and took out her brainwashed armed henchmen. When Catwoman finally got to her, Ivy didn't forgive her for killing some of her plants in the past. After a quick fight, Ivy wrapped Catwoman up in her vines, but was persuaded when she remembered that one of her plants was locked in the same vault. She let Catwoman go and made her plants rip open an entrance to the vault. When Catwoman got to the plant and her loot in the vault after taking out five TYGER Guards, she killed the plant anyway and walked out with her loot.
If Catwoman visited Ivy after the story was beaten, you could see her brainwashed guards worshipping her, and if you talk to her, Catwoman apologized to Ivy and said that it was Strange's fault. Ivy then said that she'll kill everyone, and if you continue to try to speak to her, she'll mutter aloud to herself about destroying all of Gotham City.
After Arkham City Incident
Arkham Knight Incident
Ivy has no designated lair but does spend most of her game time in the Miagani Botanical Gardens.
- Poison Ivy's Lair could only be visited by Catwoman due to the fact that the main entrance was smothered by plants so you could only Cat Crawl under the bridge to get in.
- Poison Ivy's Lair used to be a hotel until Ivy took it over with her plants.
- Poison Ivy's Lair & Penguin's Museum are the only places you could see a TYGER Guard after Protocol 10 (Not including the Challenge Maps).