The moment Mike used Blood Orb-Blood World, he was completely stunned when the entire body of the tiger transformed into a stream of blood and qi. This was the first time he had used the Blood Orb-Blood World.
When he used the Blood Orb, he found he can't use it on the opponent that are alive. So, he created Blood Orb-Blood World based on the principle of Yin-Yang Dual Enlightenment State. Creating a massive black hole with the power of blood and to suck the blood.
If his opponent isn't stronger than him, he can easily absorb the blood of the opponent. With this tiger, the case was a little different. Mike was weak if the tiger uses his Qi. But, without Qi, the tiger was weaker than Mike.
And, if Mike tries to absorb the blood, the tiger could still use the Qi to heal himself and even transform his whole body into Qi. This is what he noticed when he first slashed the arms of the tiger. Except for Darkness Swallow, he didn't have any skill to devour the Qi.