Cards

Due to the nature of the server, no card can be deemed 'rare', which means a good deal of the boss/mvp cards needed to be changed to prevent them from being too good. Likewise, several of the standard bonuses got a boost to make them more useful.

MvP/Boss cards
Amon Ra card: autocasts Kyrie Eleison Lv5 at a (1+Int/20)% rate.
ArchAngeling card: increases Hp/Sp recovery by Base Luk%.
Berzebub card: gives -20% cast time at the expense of +15% SP skill cost.
Bloody Knight card: has a 1% chance of casting Meteor Lv3 per attack.
Doppelganger card: gives a +15% stackable aspd increase.
Dracula card: steals 2% sp with a success rate of 20%.
Garm Card: has a 20% freezing chance.
Ghostring card: gives you a ghost property armor alright, but the penalty is that your natural recovery rate is diminished by 20%. Also, ghost elemental defense against physical attacks is not 75% (check Elemental Tables thread for actual values).
Golden Thief Bug Card: reduces magic damage (and Heal) by 25%, it blocks status changes which alter at least one status (base stats, walk speed, aspd, etc) which is caused by a magic skill (except Freeze/Petrify). It will also block the following skills from working: Cure, Status Recovery, Dispel, Spell Breaker. SP consumption increase is +25%.
High Wizard Card: ignores defense on magical attacks (against non-bosses), but the penalty is +100% cast times and +50% SP cost to skills. On equip, you lose 50% SP.
Incantation Samurai Card: ignores defense on physical attacks (against non-bosses), but the penalty is def -20 and def2 -20%. On unequip, you lose 50% HP.
Kiel card: gives -20% delay time at the expense of +15% SP skill cost.
Mistress card: gives a 90% chance of casting spells without need of gemstone (or Ninja elemental stones) and a 30% chance of not consuming other items (except traps and potions).
Osiris card: grants Hp/Sp healing based on how you revive: Self-revive: +25%, Resurrection: +50%, Respawn: +100%
Pharaoh card: reduces SP consumption by 30%, but increases cast and delay times by 10%.
Phreeoni card: gives perfect hit (ignore enemy flee) at the expense of -20 def, -20% flee and -20 lucky dodge.
Thanatos Card: gives piercing defense damage of both physical and magical attacks, but the penalty is def/mdef -25 and def2/mdef2 -25%.
Turtle General Card: increases damage by 20% at the expense of -10% hit.

Normal cards
Cramp card: has a 5% trigger chance, and the zeny amount is a random value between 1 and 10*(mob lv).
Cecil Damon card: raises ASPD by 10% with a -20hit penalty.
Deviling card: bonus and penalties are of 30% rather than 50%.
Elder card: increases damage against Guardians by 30%.
Enchanted Peach Tree card: casts Heal LV3, and your own Heal level affects the frequency at which it is casted.
Greatest General Card: has a trigger rate of 1% (3% for Acolyte classes) of casting Summon Spirit Sphere lv5 (Lv10 if you are a Gunslinger).
Hunter Fly card: steals 5% hp with a success rate of 20%.
Increase Soil: decreases damage from Guardians by 30%.
Lord Knight card: penalty is -30% max HP (instead of -50%)
Pirate Skeleton card: gives Discount lv7.
Sidewinder card: grants a stackable 10% double attack rate on any weapon.
Sky/Earth Deleter card: no longer stop regen and the gained bonus is dependant on the enemy's level (every 30 it gives the stated value)
Sniper card: steals 10% hp with a success rate of 20%. Reduces HP natural regen by 50%
Vitata card: gives heal lv4, the SP cost increase is 4%.

Cards that cause status effects when hit at 6% are set to 10%.
Cards that cause status effects when hit at 3% (9% if certain criteria is met) are set to 5% (15% when the criteria is met).
Cards that cause status effects when hit at 9% after a certain stat reaches 77 have an incremental rate of 5% +0.1*stat%.
Cards with stat bonuses every 18 base points now give a stat every 15.
Cards that give 5 SP every time a monster from a given race is killed now also give 5 SP from all other races (that is, 10 SP from the right race, 5 SP from the others) and the amount gained is dependant on monster level. Unequipping causes a 10% SP reduction.
Cards with bonuses that only take effect on low-refined equipment have their bonuses inverted so they provide a higher bonus with higher refine levels.
Cards that grant item-drops have been modified so the drop rate is increased by the mob's level (rate*lv/30%). Also drop rates below 10% are scaled (eg: 1% -> 3%, 5% -> 7.5%, 10% -> 11%).