The flaming shuriken didn't immediately move towards the vines but revolved around the boat to gain some momentum.
Orion wanted one decisive strike to sever the thick vines in two; otherwise, he thought they might not get another chance.
So after letting the shuriken revolve around to get enough momentum, its speed increased so fast that Orion and the others could barely see a red light passing through their vision around the boat.
'Its time.'
Orion thought as he controlled the flaming shuriken towards the two thick vines holding the boat down.
The shuriken bathed in flames passed right through the first one, completely severing the vines from the boat into two as smoke began to release from either end of the two pieces of the vines where the cut appeared.
After that, it didn't stop and passed through the second one as well, causing it to have the same result as the last one, completely cutting the vine attached to the boat in two.