While Cliff, a 27 year old young man, was visiting his grandparents, he was caught in what is called a "summoning" which took him to a forest infested with unknown creatures, he decided that in order to survive, he should be ready to brave all the dangers that would present to him, with his “drain” skill he would fight them to become stronger
High above the battlefield, Cliff unleashed his stomach's contents, expelling a torrent of acid. A brutal, merciless attack that devoured everything in its path.
As long as he could fuel his breath with mana, he was capable of producing nearly unlimited amounts of acid. The more he concentrated, the denser, more corrosive, and more terrifying the liquid became.
In the air, he wasn't much different from a dragon, except his flames were replaced by streams of acid that tore through enemy lines with surgical precision. He calculated every trajectory, carefully avoiding his own troops, but sometimes enemies close to allied lines managed to evade his fury. He didn't have the luxury of perfection.