People get rich here buy obtaining cards, or equips. Such as a Valkyrie Set. Then sell them. However, you can always go to tha_t09,10,11 to farm Stone of Sage. You can also farm other things. Just ask around for more help.
MvPs are suposed to have a lot of hp here because MvPing is a TEAM EFFORT. It requires more than one person to MvP, which is why we up'd their health and stats. All MvPs (and mini-bosses) have a 10% chance to drop a card. Only difference between mini-boss and MvPs are that mini-bosses have no health boosts so they are easily killable.
Good luck on your hunt.