Q1: What are the specific <Overflow X> rules for this card?
This card is always an inherent rule with trait: type "aquatic type".
Lv.5 MarineBullmon BT19-024 R Ultimate | Data | Mollusk/LIBERATOR <Decode (Blue Lv.4)> (When this Digimon would leave the battle area other than in battle, you may play 1 level 4 blue Digimon card from its digivolution cards without paying the cost.) [On Play] [When Digivolving] You may place 1 Digimon card with [Aqua] or [Sea Animal] in any of its traits from your hand as 1 of your Digimon's bottom digivolution card. (Rule) Trait: Has [Aquatic] Type. --- Inherited: [End of Attack] [Once Per Turn] You may play 1 level 4 or lower Digimon card with [Aqua] or [Sea Animal] in any of its traits from this Digimon's digivolution cards without paying the cost.
Lv.5 MarineBullmon BT19-024 R Ultimate | Data | Mollusk/LIBERATOR <Decode (Blue Lv.4)> (When this Digimon would leave the battle area other than in battle, you may play 1 level 4 blue Digimon card from its digivolution cards without paying the cost.) [On Play] [When Digivolving] You may place 1 Digimon card with [Aqua] or [Sea Animal] in any of its traits from your hand as 1 of your Digimon's bottom digivolution card. (Rule) Trait: Has [Aquatic] Type. --- Inherited: [End of Attack] [Once Per Turn] You may play 1 level 4 or lower Digimon card with [Aqua] or [Sea Animal] in any of its traits from this Digimon's digivolution cards without paying the cost.
Lv.5 MarineBullmon BT19-024 R Ultimate | Data | Mollusk/LIBERATOR {{Decode|Blue|4}}. [On Play] [When Digivolving] You may place 1 Digimon card with [Aqua] or [Sea Animal] in one of its traits from your hand as 1 of your Digimon's bottom digivolution card. (Rule) Trait: Has [Aquatic] type. --- Inherited: [End of Attack] [Once Per Turn] You may play 1 level 4 or lower Digimon card with [Aqua] or [Sea Animal] in one of its traits from this Digimon's digivolution cards without paying the cost.
Lv.5 マリンブルモン BT19-024 R 完全体 | データ種 | 軟体型/リベレイター ≪デコード《青Lv.4》≫(このデジモンがバトル以外でバトルエリアを離れるとき、このデジモンの進化元から、青のLv.4のデジモンカード1枚をコストを支払わずに登場できる) 【登場時】【進化時】自分の手札から、特徴に「水棲」を含むデジモンカード1枚を自分のデジモン1体の進化元の下に置ける。 〈ルール〉特徴:タイプ「水棲型」を持つ。 --- Inherited: 【アタック終了時】[ターンに1回]このデジモンの進化元から、特徴に「水棲」を含むLv.4以下のデジモンカード1枚をコストを支払わずに登場できる。