Rebalance of LK_CONCENTRATION (Concentration)

- Atk % bonus changed
   - Old: (SkillLv x 5) %
   - New: (5 + SkillLv x 2) %
- Def reduction % changed
   - Old: (SkillLv x 5) %
   - New: (5 + SkillLv x 2) %
- SP Cost changed to 20 at all skill levels
- Duration changed to 60s at all skill levels

From 1st/2nd/Transclass rebalance (2018.10)

db/re/skill_db.conf

@@ -11040,32 +11040,10 @@ skill_db: (
 	DamageType: {
 		NoDamage: true
 	}
-	SkillData1: {
-		Lv1: 25000
-		Lv2: 30000
-		Lv3: 35000
-		Lv4: 40000
-		Lv5: 45000
-		Lv6: 50000
-		Lv7: 55000
-		Lv8: 60000
-		Lv9: 65000
-		Lv10: 70000
-	}
+	SkillData1: 60_000 // Duration of SC_LKCONCENTRATION (in milliseconds)
 	FixedCastTime: 0
 	Requirements: {
-		SPCost: {
-			Lv1: 14
-			Lv2: 18
-			Lv3: 22
-			Lv4: 26
-			Lv5: 30
-			Lv6: 34
-			Lv7: 38
-			Lv8: 42
-			Lv9: 46
-			Lv10: 50
-		}
+		SPCost: 20
 	}
 },
 {

src/map/status.c

@@ -4560,12 +4560,12 @@ static int status_calc_batk(struct block_list *bl, struct status_change *sc, int
 
 /**
  * Calculates bl's Extra ATK gains from Buffs.
- * 
+ *
  * These are very specific bonus from SCs where:
  * - They show in status window ATK right side (after the + sign)
  * - They are given by SCs, but they work like equipment's ATK bonus
  * - They are not linked to the weapon attack value
- * 
+ *
  * @param bl unit whose status is being calculated
  * @param sc unit's SC list
  * @returns Value of Extra ATK conceded by buffs
@@ -8374,7 +8374,7 @@ static int status_change_start_sub(struct block_list *src, struct block_list *bl
 				} else {
 					val2 = 0; //0 means that STR, DEX and INT should be halved
 				}
-				
+
 				val1 += bonus; // Officially, val1 is incremented (for us, this doesn't make a difference)
 				break;
 			}
@@ -8430,9 +8430,14 @@ static int status_change_start_sub(struct block_list *src, struct block_list *bl
 					total_tick += total_tick / 10;
 				break;
 			case SC_LKCONCENTRATION:
-				val2 = 5 * val1; // ATK% Increase
 				val3 = 10*val1; //Hit Increase
+#ifdef RENEWAL
+				val2 = 5 + 2 * val1; // Batk/Watk Increase (@TODO: BATK/WATK or ATK%?)
+				val4 = 5 + 2 * val1; // Def% reduction
+#else
+				val2 = 5 * val1; // ATK% Increase
 				val4 = 5 * val1; // Def% reduction
+#endif
 				sc_start(src, bl, SC_ENDURE, 100, 1, total_tick, skill_id); // Endure effect
 				break;
 			case SC_ANGELUS: