Seymour Natus versus bosses playlist: http://www.youtube.com/watch?v=akW2IyDw1iU&list=PL6dTt7vXJ8lQ8tdz3XSB4CZn4rVE-6GQZ
Walkthrough's description and rules: Welcome to my "hackthrough". Here my favorite boss, Seymour Natus, will fight solo against every enemy of the game, except random encounters and most of the monster arena. Batches will be in a single video. All optional enemies will be recorded after the main storyline with the exceptions of Lord Ochu, Belgemine's Ifrit (pre-Remiem) and Belgemine's Ixion (pre-Remiem). His stats begin at 499 HP, 999 MP and 1 for everything else (technical limitations aside). Before Seymour Guado's first battle, they'll be raised by 100 HP, 0 MP and 1 for every other stat. From it until Jecht's battle, they'll increase by 200 HP, 0 MP and 2 for all others. If Seymour Guado is in the party he'll summon Seymour Natus on his first turn, otherwise the fastest character will. Grand summoning can't be used. Once Seymour Natus is there everybody else will use eraser on itself as soon as possible. The hack-item appearance will be used once in every battle. Spell hack-items won't be used if silenced. Turbo ethers can only be used if osmose ("osmosa") has targeted every enemy at least once, and this resets if said enemy drains his MP. Overdrive and items will be restored before every video. After killing Braska's Final Aeon, anything may change at my discretion.
Maximum HP: 1399
Maximum MP: 999
All other stats: 10
Auto-abilities: First strike, no encounters, one MP cost, piercing, berserkproof, confuseproof, deathproof, stoneproof.
Overdrive mode: Aeons' overdrive mode.
Special abilities: Steal, pray, cheer, aim, focus, reflex, luck, jinx, lancet, threaten, provoke, doublecast.
Black magic: Firaga, thundaga, waterga, blizzaga, drain, flare, ultima.
White magic: Curaga, scan, nulblaze, nulshock, nultide, nulfrost, esuna, full-life, hastega, slowga, shell, protect, reflect, dispel, regen, holy.
Items and hack-items: Turbo ether, echo screen, holy water, berserk, confuse, mute ball, blind, sleep, mind blast, mega death, gravija, osmose ("osmosa"), curse, tera-graviton, biora, lance of atrophy, appearance, summon (disallowed), eraser (disallowed), thundaja (disallowed)
Other abilities: Energy blast, stand by, talk, shield, boost.
Custom recordings: Would you really love to see something that's not yet on my channel? I consider requests regarding Final Fantasy X (NTSC-J) videos or Final Fantasy X (PAL-Spanish) videos, however I'll only use the Spanish version if said video/s require/s using the debug room, only accessible in this version. I won't accept requests which are cheat-free/hack-free (please, ask anybody else) or longer than 15 minutes of video unless it's something I'm truly interested in. Do keep in mind that I'll take my time, since I don't have wi-fi and I can't pay so much internet café! As long as my phone is working I'll answer comments, though.
WARNING: I noticed that there are several accounts here in YouTube reuploading my videos. They include a hack-tools downloading link or a few at the very beginning of the description and leave everything else intact, pretending they were me. The true guy recording and originally uploading these videos is me, Seymour Natus. Accounts with different names are fake. Here's the link to my channel: http://www.youtube.com/channel/UCSaKSws33jcp_2txPlzlncg
Stuff used: Final Fantasy X (NTSC-J), PCSX2, MyMc, FFXED, OmniConvert, PCSX2CE, x264vfw - H.264/MPEG-4 AVC codec, VirtualDubMod, free video to flash converter (by DVDVideoSoft)