Couple of memorable parts were A more extensive O&S fight and fighting artorias on an equal playing field (i.e myself also being afflicted by the abyss) Near the end the difficulty is a bit too much, as you have to beat every single boss to face Gwyn, and I didn't have the patience to keep going, but the mod is well done and worth a try. Also changes the overworld and story progression in an interesting way. Scorched contract: Every boss you kill gives a different permanent effect, rule of thumb is the harder the boss the more difficult the effect is to deal with.
Some minor changes other than rearranging too. Game is reshuffled, but not too much harder. Prepare to die again: Kind of like a zelda master quest type thing.
There are a few full-game changing mods, nothing really 'essential' since after DSFix the game is pretty comfy on PC.
