Showing Heart
Not knowing how many opponents he still had to face was a psychological nightmare for Leo.
He could not plan strategically enough on how much stamina/mana to conserve and had to look at every wave that he faced as if he still had potentially more opponents left.
This made facing the 14th even more challenging for him than it was supposed to be, as on one hand he had already made plans on how to handle the 15th one his mana reserves returned above 80%.
However, for him to conserve his mana while saving his stamina meant that his HP had to take a hit.
Hence, just like the 13th wave where he lost 21% of his HP, the 14th saw him lose a further 19%, dropping his overall HP to just over 31% by the time the 15th wave arrived.
Naturally, the reactions to him finally slowing down were insane on the global forums, as the monotonous sequence of him dominating every wave seemed to have finally broken, giving the viewers some much needed excitement.