This kinda explains why I cant get much farther than the depths. My Isaac never gets many upgrades/items. Everyone who gets far has a waaayy crazier looking Isaac than mine ever gets.
- Make it a priority to open gold doors. These rooms always have special items.
- Check in arenas, there's occasionally syringes or other items.
- Look for secret areas - they usually contain money and sometimes items. They're usually found in empty areas on the map surrounded by a few other rooms.
- Use slot machines and give money to beggars, you can get a lot of good stuff that way. Beggars can really give you some amazing stuff if you give them enough money.
- You can get some good stuff by killing minibosses.
- Sometimes it can be worth selling your hearts for items. Personally, I think it's worth it for the shovel, laser eye and Necronomicon.