i couldnt do it with trish (no matter how hard i tried). i did it last night with dante. it took me about 3 hours (maybe a little more). trust me, having a full item inventory, along with a maxed out Submachine gun, rocket launcher, and Vendetta. mainly use the rocket for damage (it also works for crowd control). always go for the Flying Goats first (the blasts should keep most of the ground enemies off you), then go for the ground goats, and (if they are there in the same fight) go for the saw throwing guys next. the other enemies are usually easily dodged or kept at by with the rocket launcher. when you fight the white wolves (and you will get into rooms where you fight nothing but them) it is best to get into a corner, let them pile up around you, DT and start swinging (DONT shoot your gun, it will just eat up your DT and wont do enough damage to the group). with swinging, you can hit 3 and 4 wolves at the same time. also, primarily stay with the Healing Heart. trust me, unless you have full HP, it is better in the long run. finally, on stages with the regenerating Savages, use the rocket launcher to get them weak, and when they have half of one bar left of HP, switch to DT to finish this fast with gun fire. they regenerate too quickly to do anything else. another useful thing to do with them (although it is bloody slow) is to kill all but one, keep weakening it with the rocket launcher (and thus building your DT) and let it regenerate. you can do this over and over until your DT is full, and even use the DT to heal yourself, then fill it again. it takes time, but it does help.
with a full inventory of items, figure you can use 10 Small Devil and Vital stars, and 3 Large ones every 30 floors. try to save as much as you can for the final push. for the last 10 floors, i had about 13 small devil stars and 4 large ones. you still have to be careful, but this let me rush through the final floors a little bit. also, if your games graphics start glitching (mine did around floor 7500) dont worry. it can make it hard to see, but just keep going. --- Gamertag: The Unus Mundus PSN: cowboybbp1