General Things:

Stats

Strength(Str): increases hp, the physical attack/defence and the physical balance
Intelligence(Int): increase mp, the mental attack/defence and the mental balance

They do not affect hit/parry rate. Hit/parry rate increases by one on every level up. Each level you get you gain 5 stats. 2 are distributed automatically, 1 into str and 1 into int. The other 3 stats can be distributed manually.

Physical/mental balance

They factored into the damage you done so the higher it is the more damage you'll do. For example, a physical attack of 100-140 and a physical balance of 80% will give you a damage range from 80-112. It's more complicated than this but this is the general idea.

Hit/Parry rate

There's NO DODGE in SRO. REPEAT NO DODGE, IN THE PAST, PRESENT, OR FUTURE. >_< Hit/parry rate simply increase the chance of doing a high damage in attacking and receiving a lower damge, under the damage range. Take the damage range from above: 80-112. The higher the hit rate, the more likely you'll do damage closer to the maximum 112. If that's the damage you're receiving, the higher the parrying rate the more likely you'll receive damge closer to the minimum 80.

But sometimes I see a red "block" pops up and I receive no damage!

That's because you're holding a shield. A shield have a blocking rate, will equals to the parcentage you'll block an attack. So for a blocking rate of 10, you'll have 10% blocking the attack and rececive no damage. I currently don't know if it'll block skills also.

Equipments

There're five classes of weapons
Swords: can equip shields, mental based, double attack
Blades: can equip shields, physical based, double attack, lower critical
Spears: two-handed, highest mental power, higher critial
Glavies: two-handed, highest physical power, Slow weapon
Bows: two-handed, long range, fast attack, relative low physical/mental power


There're three classes of body equips:
Armor: high physical defence, low mental defence
Garment: high mental defence, low physical defence
protector: balance in physical and mental defence


Armor and protector equipments can be mixed but garment cannot mix with either of them. In addition, wearing full protector/garment sets will give you bonus:
full protector set: -10% mp usage, +10% moving speed
full garment set: -20% mp usage, +20% moving speed

Armor sets does not gives any bonus.

Blue equipments are equips with extra stats. There can be one to several stats on the blue equips.
Power and Mental: simply adds the number of power/mental points
Reduce status: reduce the duration of a status by a percentage, there're five types: freezing/frostbite, burn, shocked, poison, zombie
Immortal: When upgrade fails prevents equipments from breaking(losing the item)
Steady: When upgrade fails prevents equipemtns from losing durablity
Lucky: Increase chance of sucessful upgrade
Immortal, steady and lucky has a number of times use, and when the number reach zero the stat is gone.
Unrepairable: Cannot be repaired, durabily is 4 times larger than normal. (never seen any number other then 4 times)


Special shoes (I believe that's a bad translation)
There's a phyical and mental special shoes with every equips. This number determines the power/defence increased in an upgrade. It is said that 10% special shoe equals to 1 power/defence increase but this is not tested in the english SRO.

Degrees
Equipments comes in sets. Within a set there's 3 different leveled equips for each body part. A set is then given a degree based on the level of the equipments. So the first set (lvl 1- is degree 1, second set (lvl 9 -16) is degree 2, etc. This is only use in upgrading where you need to have the same degree lucky powder to boost in chance of sucess.

Status effects
Status effects are given an effect number, and there's an effect number with every status effect skills. Using pills or healing qi simply reduce the amount of effect number, and then the effect number is equal to zero the effect is cured For example, if you're burned for effect 60, and you take a piil which heals status of effect 36, you'll still have the status for effect 24. It looks like effect points affect the status duration, but i'm not sure.

Now the status effects
Burn: you lose some hp every few seconds. hp loses are random but higher level burn does more damage. The random burn sometimes will do as much as 10x damage.
Electric shock: Lowers parry rate, thus increasing the chance of doing higher damage. This does NOT stun or slows you in anyway.
Freezing: Ah, the pvp status effect king. It renders you immobile, so your opponent can hit you without fear of retaliation.
Frostbite: Slows you down and decreses your attack speed.
poision: same as burn but damage taken is constant.
zombie: when any hp skills or potion is used, hp is decreased instead of healing you.
Damage:
White Numbers: This is showing the amount of damage you are giving to the enemy.
Red Numbers: This is showing the amount of damage you are taking.
Orange Number: this is showing damage being taken by fire status.
Greenish Yellow Numbers: This is showing the damage being taken by poison status.
Block: This shows that the damage was totally negated. Only characters with shields can block.

Is there a stun effect?
Yes in the spear skill tree the fourth skill (lvl 14) has a chance to stun. When stunned you'll glow yellow and a yellow tornado-like spiral will appear on your head. Unlike other effects stun does NOT allow item usage so unless you got a healer behind you you're stunned for the whole time.

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