Don't turn
Quinn only had a short amount of time to test the capabilities of the Roseus tree beforehand, but now, forced into this real battle situation, he was quickly picking up new tricks and skills that were helping out with the fight against their enemy.
For example, while using Full Control on the Demon tier tree itself, he could still continue to give it simple commands as if he was giving someone partial control orders. What this meant was that the Vampire Lord could focus on certain parts on the island to help boost creatures and fight against the enemy.
The masked vampires were getting frustrated as more and more beasts had been coming out of nowhere, since the tree's roots had been marking new one whenever one died off.
Another difference between the tree and the Demon tier amulet was in regards to the energy transfer. The tree actually never seemed to run out of energy, it seemed more like it was allowing the beasts to borrow its energy.