I, Kevin, Always Want People to Send Me Something

"I'm Kevin, a warrior bearing the mark of Salvation. Saving the world is no easy task, but just send me 50 and I'll go retrieve the Judgment of Shamash! Ahem, sorry, force of habit. I'm Kevin, a Flame-Chaser bearing the mark of Salvation. Saving the world is no easy task, but just send me one Chiyou and I'll regain a tenth of my full strength. Then I'll help you fulfill your dream. Of course, if you don't have a Chiyou, a few Holy Grails will do."

"Hm? Never heard of anyone called Kevin? No problem. If you prefer a name you might know, you can call me Merlin or God. Just give me, like, a billion years to prepare, or wait for some world-ending disaster to erupt so I can switch to the Savior class, and your wish should be easy to fulfill."

P.S. Maybe a crossover...?