Seeing that Elizabeth was looking at Rex that he was carrying, Marco let go of Chase's hand and stopped sizing him up, then handed it over to her.
"Adam said, me give Elizabeth dog. Poison bad-bad for dog, and you help,"
Elizabeth had already sensed something ominous within the dog that was consuming it internally, and instantly after monitoring the dog, she understood what Adam had meant by saying there was something that could help her grow stronger.
The poison within Rex was extremely powerful and unique, able to adapt, grow stronger and mutate.
If she was able to somehow understand, absorb and be able to wield the poison, her power would greatly increase and her attacks would become much more deadly than they already were.
She was unsure where exactly the dog beast come from, but she was impressed and amazed by how strong its body was and how well it was able to fight off the poison.