Cyndaquil. Invaluable help for Bugsy and Jasmine (that is the Steel leader, right)?
Though let me just say that i just experienced a rather violent tantrum from that damned Rival fight in Azalea town. I walked right into that trap by accident, even knowing it was there, and lost an hour of grinding to that fucker (which was still worth less than the severe money loss), and then resolved to fight my way through that battle by fiat, considering that i had no appropriate move types to deal with him, just Peck the Ghastly to death, start an Uproar against Croconaw till he takes Hoothoot down, quick-attacking Croconaw with Quilava until it goes down (because its stupid enough to keep using Scary Face and not water gun), then crushing Zubat with fire.
Monster Hunter: pissing me off since 2010.
