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Monster Rancher 2 In-Depth Combining Guide
Advanced technical details

MR2DX Info to be aware of:
  • Contains the 1999 version's unobtainable 1% bug (Still obtainable if there are two 1%s), but DX also a 2% & 3% bug that only gives base stats.
  • When combining, a Baby's Base starting nature determined solely by the Baby's breed baseline. The base starting nature can't be altered in DX.
  • Nature from Disc Chips in combining is bugged, giving little or no benefit in DX.
Research by SmilingFaces96 - Original documentation here

This document is intended to reveal the lower level details related to combining. Most of this is already revealed on legend.com through previous work by Alchius and others. This document will just add some of the percentage information and actual numbers used within the game. The assumption made in this document is that you have done the lab combining process at least once and have somewhat of a general understanding of Monster Rancher 2 concepts related to attribute values and their gains, techniques, battle specials, form, nature. In addition, you already know what are Disc chips and some of the other combining items. Something that is not really touched on in this document is that the new baby monster that is generated will start with a pre-determined base data – all this data can be gathered from legend.com. All the explained processes below are then applied to the base data to give the final baby monster data. The following is the table of contents for these processes. The 1st section is rather long, so if you don't care how the combining percentages are determined, just skip on ahead.

  1. Combining Percentage of Monster Selection
  2. Combining Influence of Special Items and Monsters and Monster Selection
  3. Combining Order and Attribute Calculations
  4. Dadge's Message to the user about Combination
  5. Inherit Parent Techniques and Use Number
  6. Inherit Parent Form and Base Nature
  7. Inherit Parent Battle Specials
  8. Parent Training Bonuses are not inherited
  9. Add Attribute Combining Item Effect
  10. Available Combining Items through Cheat Only

 


  1. Combining Percentage of Monster Selection
    1. So, the first thing to do is to create the monster possibilities. The best way to do this is to show them in a table. So your parent monster #1 is a M#1/S#1 and your parent #2 is a M#2/S#2.
    2.  #1#2#3#4#5#6#7#8#9#10#11#12#13#14#15#16
      MainM#1M#1M#1M#1S#1S#1S#1S#1M#2M#2M#2M#2S#2S#2S#2S#2
      SubM#1S#1M#2S#2M#1S#1M#2S#2M#1S#1M#2S#2M#1S#1M#2S#2

    3. If the S#1 or S#2 is a marked “???” (special monster), then the M#1 or M#2, respectively, will replace it.
    4. Next we remove the two entries that cannot be created which are entry #5 and entry #15. You cannot immediately create the inverse of either parent monster.
    5. The next part of the process is to start assignment of the combining strength values to each of the entries. There are 2 different kinds of strength values: Positional strength and Main Type monster strength. Alchius, when discussing this (discussion on legend.com), referred to these strengths as the monster's blood type. And that the Main Type monster blood-types had different combining strengths – Pixie and Golem being the strongest. The Main Type monster combining strength values are below.
    6. Monster Main TypeCombining Strength
      Ape2
      ArrowHead3
      Bajarl1
      Baku4
      Beaclon4
      Centaur4
      ColorPandora1
      Dragon7
      Ducken1
      Durahan5
      Gaboo2
      Gali6
      Ghost1
      Golem10
      Hare6
      Henger4
      Hopper6
      Jell6
      Jill3
      Joker3
      Kato2
      Metalner1
      Mew2
      Mocchi4
      Mock1
      Monol6
      Naga6
      Niton4
      Phoenix1
      Pixie10
      Plant6
      Suezo6
      Tiger6
      Undine1
      Worm6
      Wracky5
      Zilla2
      Zuum9
    7. So, next we need to populate our strength values into a table. For the purposes of this, we will combine a Tiger/Monol with a Dragon/Tiger. Please note that the positional strength is always the same. For the first 4 entries, we use Tiger as the main which is 6, then next 3 entries are Monol which is also 6. The following 4 entries are Dragon which is 7 followed by 3 Tiger entries again which are 6.
    8.  #1#2#3#4#6#7#8#9#10#11#12#13#14#16
      Position44843424222211
      Main66666667777666

    9. Based on whether the combination is from the same monster input (i.e. M#1/M#1 or S#2/S#2), we add or multiply the positional strength with the main type strength. See the table below.
    10.  #1#2#3#4#6#7#8#9#10#11#12#13#14#16
      Function+xxx+xxxx+xxx+
      Strength102448249241228149141267

    11. Next we add in our bonus strength from combining. The bonus strength value is 5. The bonus strength comes from the Monster combining items. Only the Monster Main type is considered for this bonus. So, when the Monster Disc Chips Combining item matches the Monster Main Type or the Taurus Horn is used and the Monster Main type is a Centaur, a bonus is applied to those combinations that have a main type that match. For an example we chose to use Monol Disc chips and apply it to above. So, entries #6, #7, and #8 get the bonus, since their monster main types are Monol.
    12.  #1#2#3#4#6#7#8#9#10#11#12#13#14#16
      Bonus00005550000000
      Strength1024482414291728149141267

    13. Next we eliminate the entries that don't exist as a monster combination. For the purposes of our example that would be a Tiger/Dragon and a Monol/Dragon. Entries #3 and #7. So, we eliminate them. I will use D for Dragon/T for Tiger/M for Monol to show the combinations that are left below.
    14.  #1#2#4#6#8#9#10#11#12#13#14#16
      MainTTTMMDDDDTTT
      SubTMTMTTMDTTMT
      Strength102424141728149141267

    15. Next we combine (add) the strengths of the like monster entries. So, #1, #4, #13, and #16 which are T/T are combined. #2 and #14 which are T/M are combined. #9 and #12 which are D/T are combined.
    16.  #1#2#6#8#9#10#11
      MainTTMMDDD
      SubTMMTTMD
      Strength5330141742149

    17. Now, we sort the entries by strength from highest to lowest.
    18.  #1#9#2#8#6#10#11
      MainTDTMMDD
      SubTTMTMMD
      Strength5342301714149

    19. Next we add up all the strengths to get total strength, which is 179.
    20. Now we take each strength value and multiply by 1000 and then divide by 179 rounded down.
    21.  #1#9#2#8#6#10#11
      MainTDTMMDD
      SubTTMTMMD
      Strength29623416794787850

    22. Now we add 5 to each strength value for rounding purposes and then divide by 10 rounded down.
    23.  #1#9#2#8#6#10#11
      MainTDTMMDD
      SubTTMTMMD
      Pct3023179885

    24. Now we add the percent together to see if it is 100%, which it is.
      1. If it is less than 100%, starting with the now second place entry moving from left to right (so #9 towards #11 in our example above), we start adding 1% to each entry until 100% is reached.
      2. If it is more than 100%, then starting with the first place entry, subtract the amount necessary from it to get down to 100%.

     


  2. Combining Influence of Special Items and Monsters and Monster Selection
    1. During the combining process, if any of the following specific items are used, then the monster pure-breed of that monster will be generated at a 100% combining percentage rate.
    2. Combining ItemPure-Breed Produced
      Big BootsJill
      Double-edgedDurahan
      Dragon TuskDragon
      Fire FeatherPhoenix
      Magic PotBajarl
      MaskJoker
      Quack DollDucken
      SpearCentaur
      StickGhost
      Undine SlateUndine
      Zilla BeardZilla

    3. During the combining process, if a Silver Suezo is combined with a Broze Suezo, then a Gold Suezo will be generated at a 100% combining percentage rate.
    4. If none of these combining items are used, then the percentages calculated from section 1 above will be used to determine the monster chosen. There is a bug in the software during this random number based selection process that effectively reduces the last placed monster's percentage by 1%. So, if the last placed monster percentage is 1%, then it becomes 0% and cannot be selected. The stored percentage used for monster attribute offset calculations if the last placed monster is selected is still the calculated value above.

     


  3. Combining Order and Attribute Offset Calculations
    1. Baby Monster Attribute Base Data Offset
      1. This is the calculation for the attribute (lif/pow/int/ski/spd/def) offset from the baby monster base data before any combining order effects or combining percentage effects are applied.
      2. Actual = current attribute value of parent monster 1 or 2
      3. Base = base attribute value of parent monster 1 or 2
        - If this is a special monster (/???), then the pure-breed stat is used for the base
      4. (2 x (p1_actual - p1_base) + (p2_actual - p2_base)) / 3 – rounded down
        - If the value is less than 0, then 0 is used for the base offset.
    2. Parent #1/#2 Attribute Order
      1. Attributes are ordered based on Parent attribute gains (0-4) and Parent Attribute values.
      2. Adjusted Attribute Value used for the ordering is (Attribute Gain x Attribute Value), not limited
      3. The order is from greatest adjusted attribute value to least adjusted attribute value
      4. If there is a tie among the Adjusted Attribute Values, then the parent base data attribute order is used to determine the order
      5. If there is a tie among the base data, then the order priority is Defense, Speed, Skill, Intelligence, Power, Life
    3. Baby Monster Attribute Order
      1. Attributes are ordered based on the Base Attribute Gain Values
      2. If there is a tie among the gain values, then the attribute base data is used
      3. If there is a tie among the base data, then the order priority is Defense, Speed, Skill, Intelligence, Power, Life
    4. Attribute Order Alignment and Count
      1. The baby monster attribute order is compared to both parents. Each ordered position is compared. If it matches both parents, then a matching counter is incremented as well as the attribute matching the order is marked as a match.
      2. Possible total values that match are 0,1,2,3,4,6
    5. The Percentage of the base data offset from section a, Baby Monster Attribute Base Data Offset, above that is passed on to the intermediate baby monster attribute data offset is based on the two pieces of information collected from section d, Attribute Order Alignment and Count. For the attribute match, each percentage is calculated separately based on a different random number. The selected percentage is then multiplied by the base data offsets, round down to get the intermediate offsets.
    6. Count of Total Data that Matches012346
      Attribute Matches Order15%30%-39%40%-49%50%-59%60%-69%70%-79%
      Attribute Does Not Match Order15%15%15%15%15%15%

    7. Once the intermediate baby monster attribute base data offsets have been determined, evaluation of the percent chance of the generated baby monster is then applied to the offsets. The percentage of the intermediate attribute base data that will be kept is as follows. The 1st two rows are the percentage range for the percent chance of the generated baby monster. The last row is the percent of the attribute offset that will be kept. The selected percent is then multiplied by the intermediate base data offset to get the final base data offset.
    8. Lower1%2%4%8%15%30%50%75%100%
      Upper1%3%7%14%29%49%74%99%100%
      Percent100%90%80%70%60%50%40%30%20%

    9. Once the final baby monster attribute base data offsets are determined, they are added to the baby monster's base attribute data to determine its starting attribute values.
    10. In addition, if a combining item affects a starting attribute, it will be added after these offsets have been applied.

     


  4. Dadge's Message to the user about the Combination
    1. Refer back to section 3.b Parent #1/#2 Attribute Order. When evaluating whether the combination will be good or not, Dadge compares the parent's attribute order to determine how good the combination is going to be. Dadge is not able to compare it to the baby because he does not know what baby is going to be produced.
    2. The possible total matching attributes are 0,1,2,3,4,6. Dadge responds with the corresponding message based on this total. His response is in the following table.
    3. As an exception, Dadge will respond with “This one's all up to you”, when both parents are identical.
    4. Number of Matching AttributesWhat Dadge Says
      0This one's all up to you.
      1This combination doesn't look so good. I can't recommend it.
      2The prospect here is unsure.
      3This prospect is fine... It will probably work out.
      4The prospect of this combination is good. You can look forward to it.
      6The prospect of this combination is great. It can't go wrong unless something weird happens.

    5. So, what could go wrong, well none of the parents attribute order matches the baby and you get a poorly created baby monster in terms of percentage of attribute value passed.

     


  5. Inherit Parent Techniques and Use Number
    1. The baby monster starts out with their default techniques, which is two of them.
    2. There are two methods to inheriting parent techniques. The method depends upon whether the Parent #1 main monster type matches the baby monster main type. All inheritance for techniques is based on Parent #1.
    3. Baby Monster Main Type does not match Parent #1 Main Type
      1. As for the technique inheritance, for each errantry location (that is not Kawrea) where at least one technique has been learned, the new baby monster will get the first priority technique of that errantry location learned.
      2. No more than one technique from each location can be learned this way. Therefore, the maximum techniques inherited this way are 4. So, your new baby monster can start out with 6 techniques.
      3. Since the two monsters don't share the main type none of the technique use numbers will be transferred to the baby monster.
    4. Baby Monster Main Type does match Parent #1 Main Type
      1. As for this technique inheritance, the amount of techniques that can be inherited is calculated as follows: Technique Inheritance Total = Number of Parent #1 Techs - Number of Parent #1 Special Techs - 2 Basic Default Techs. Take the (Tech Total x 2)/3 – rounded down. This is the amount of Techs that can be inherited from Parent #1. As an example, let's parent #1 has 3 special techs and 12 total techs. So, 12 - 3 - 2 is 7. 7 x 2 / 3 rounded down is 4. So, in this example, the baby would inherit 4 of the parent #1 techs.
      2. The technique pool of techs that can be inherited from follow the same grouping method as above. The pool of techs to choose from for inheritance are Parent #1 Techs, with the special techs removed as well as the 2 basic default techs removed.
      3. The tech pool is randomized as many times as there are techniques in the pool in the following way. Take Pool entry #1 and a random entry and swap them. Take Pool Entry #2 and a random entry and swap them. Take Pool Entry #3 and a random entry and swap them. Take Pool Entry #... and swap them, until you go through all the pool entry #'s. The following is an example with only two pool entry's in order to explain situations that can occur. Pool Entry #1 is Tech1. Pool Entry #2 is Tech2. So, take Pool Entry #1 and swap with a random entry, which just so happens to be Pool Entry #2. So, now Pool Entry #1 is Tech2 and Pool Entry #2 is Tech1. Now, Take Pool Entry #2 and swap with a random entry, which just so happens to also be Pool Entry #2. So, the new order is still Pool Entry #1 is Tech2 and Pool Entry #2 is Tech1.
      4. Now each technique in the tech pool is checked to see if it meets the sub type requirement for learning the technique. If it does not it is removed from the pool.
      5. Now, check to see how many techniques are left to be learned (value obtained from i., if it is 1 or greater then proceed with inheriting techniques; otherwise, proceed to inheriting use numbers.
        1. Now the inheriting begins, take the next entry in the pool (starting with entry#1) and learn it. Decrement the number of techniques left to learn.
        2. If the newly learned tech also has a required technique to learn it at an errantry, then also learn that technique as well and decrement the number of techs left to learn.
        3. Repeat the above two steps until you have no techniques left to learn.
        4. Due to inheriting requirement techniques you may find that you can inherit one extra technique during this process if the last tech learned also has a required tech. You may also find, in triple tech chains that you may inherit chain tech#2 and chain tech#3, but don't inherit chain tech#1.
      6. Now, take the parents technique use numbers for the baby inherited techniques including the default starting techniques and transfer them to the baby technique use numbers.

     


  6. Inherit Parent Form and Base Nature
    1. Form
      1. First, create the form total according to the following equation:
        Form Total = 2 x Parent #1 Form + Parent #2 Form
      2. If either parent Form is 0, then divide the Form Total by 2; otherwise, divide by 3.
      3. Take the decimal results and round toward 0 (-0.4 -> 0, 0.4 -> 0) to get Parent Combined Form.
      4. Baby Monster Form = Parent Combined Form
    2. Base Nature
      1. Calculate Parent Nature by adding the trigonometry calculated nature adjustment to its base nature for each parent.
      2. Create the nature total according to the following equation:
        Nature Total = 2 x Parent #1 Nature + Parent #2 Nature
      3. If either parent Nature is 0, then divide the Nature Total by 2; otherwise, divide by 3.
      4. Take the decimal results and round toward 0 (-0.4 -> 0, 0.4 -> 0) to get Parent Combined Nature.
      5. Now apply the following formula to get the final Baby Base Nature:
        - Baby Base Nature = (Baby Default Base Nature + Parent Combined Nature)/2

     


  7. Inherit Parent Battle Specials
    1. The battle specials from both monster parents can be inherited and added to the default battle specials of the baby monster. The chance for inheritance is based off of whether both parents have it, parent#1 has it, or parent#2 has it. The following table lists the percentage chance of inheritance for each battle special.
    2. Battle SpecialBoth ParentsParent#1Parent#2
      AngerCan't be inheritedCan't be inheritedCan't be inherited
      Ease80%40%20%
      Fight80%40%20%
      Fury50%25%10%
      Grit80%40%20%
      Guard100%50%30%
      Hurry100%50%30%
      PowerCan't be inheritedCan't be inheritedCan't be inherited
      RealCan't be inheritedCan't be inheritedCan't be inherited
      UnityCan't be inheritedCan't be inheritedCan't be inherited
      Vigor100%50%30%
      Will100%50%30%

     


  8. Parent Training Bonuses are not inherited
  9.  


  10. Add Attribute Combining Item Effect
    1. After all the data has been populated based on the effects above, then the item that was used in combining will be utilized to add an additional effect, if there is one. The following table lists the effects for the combining item.
    2. ItemEffect
      Ape Disc ChipsAdd +1 Parepare Errantry Training Bonus
      Arrow Head Disc ChipsAdd Guard Battle Special
      Bajarl Disc ChipsAdd Vigor Battle Special
      Baku Disc ChipsSize +50
      Beaclon Disc ChipsAdd +1 Pull Drill Training Bonus
      Big FootstepLife +10, Defense +10
      Centaur Disc ChipsAdd +1 Mandy Errantry Training Bonus
      ColorPandora Disc ChipsSpoil +50
      Crabs ClawSkill +50, Defense +50
      Dragon Disc ChipsAdd Fury Battle Special
      Ducken Disc ChipsSpeed +50
      Durahan Disc ChipsAdd +1 Domino Drill Training Bonus
      Gaboo Disc ChipsAdd Fight Battle Special
      Gali Disc ChipsOverall Nature +50 (Done through modification of the nature adjustment value)
      Ghost Disc ChipsAdd +1 Dodge Drill Training Bonus
      Golem Disc ChipsPower +50
      Hare Disc ChipsAdd Grit Battle Special
      Henger Disc ChipsAdd +1 Shoot Drill Training Bonus
      Hopper Disc ChipsSize -50
      Jell Disc ChipAdd +1 Endure Drill Training Bonus
      Jill Disc ChipsAdd +1 Papas Errantry Training Bonus
      Joker Disc ChipsOverall Nature -50 (Done through modification of the nature adjustment value)
      Kato Disc ChipsAdd +1 Meditate Drill Training Bonus
      Metalner Disc ChipsFear +50
      Mew Disc ChipsAdd Hurry Battle Special
      Mocchi Disc ChipsFame +50
      Mock Disc ChipsTotal Life Weeks +10
      Monol Disc ChipsDefense +50
      Naga Disc ChipsSkill +50
      Niton Disc ChipsAdd +1 Swimming Drill Training Bonus
      Old SheathDefense -10
      Phoenix Disc ChipsAdd +1 Kawrea Errantry Training Bonus
      Pixie Disc ChipsIntelligence +50
      Plant Disc ChipsTotal Life Weeks +10
      Suezo Disc ChipsAdd Ease Battle Special
      Taurus' HornOverall Nature +25 (Done through modification of the nature adjustment value)
      Tiger Disc ChipsAdd Will Battle Special
      Undine Disc ChipsAdd +1 Studying Drill Training Bonus
      Worm Disc ChipsLife +50
      Wracky Disc ChipsAdd +1 Leap Drill Training Bonus
      Zilla Disc ChipsAdd +1 Torble Errantry Training Bonus
      Zuum Disc ChipsAdd +1 Run Drill Training Bonus

     


  11. Available Combining Items through Cheat Only
    1. The following combining items exist in the items data of the code, but are not accessible in the MR2 game through normal means.
    2. ItemEffect
      Red DNA CapsuleCreates Pixie/??? (Poison)
      Yellow DNA CapsuleCreates Pixie/??? (Mia)
      Pink DNA CapsuleCreates Mocchi/??? (GentleMocchi)
      Grey DNA CapsuleCreates Dragon/??? (Moo)
      White DNA CapsuleCreates Mocchi/??? (White Mocchi)
      Gold DNA CapsuleCreates Suezo/??? (Gold Suezo)
      Black DNA CapsuleCreates Golem/??? (ForwardGolem)
      This page was last modified: November 13 2023
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