Leon used Telekinesis and the ring of gravity to counter Stagnation of the ancient undead Trent, but the difference in power was too big. Since he also had to use that on Darya, the number of his attacks decreased a lot.
"This presence... you are not Donan." The undead Trent said. "Another presence is similar to his... a descendant? That fool... he said that none would approach this place."
That monster was truly resilient. It was receiving Leon's attacks, it was talking and was able to keep its concentration to cast spells. Despite having its body being burned by magma.
"Tsk... let's see if you can endure this." Leon clicked his tongue.
Leon stopped shooting Magma Spears for a while and then concentrated, a few seconds later, a massive lightning bolt fell from the top of the cave hitting the undead Trent. Stagnation effects disappeared, and then Leon and Darya had some room to breathe while the tree was letting some smoke out of its body.