Q1: If cards that are targets of this effect are revealed from the deck, do I have to add as many cards to my hand as possible?
Yes, you must add as many cards to your hand as possible.
Q2: What does this card's (Rule) mean, exactly?
This is a special rule for this card that always treats it as if it also has the Aquatic type trait.
Lv.3 Sangomon BT19-017 U Rookie | Data | Mollusk/LIBERATOR [On Play] Reveal the top 3 cards of your deck. Add 1 card with [Aqua] or [Sea Animal] in any of its traits and 1 card with the [LIBERATOR] trait among them to the hand. Return the rest to the bottom of the deck. (Rule) Trait: Has [Aquatic] Type. --- Inherited: [End of Attack] [Once Per Turn] Gain 1 memory.
Lv.3 Sangomon BT19-017 U Rookie | Data | Mollusk/LIBERATOR [On Play] Reveal the top 3 cards of your deck. Add 1 card with [Aqua] or [Sea Animal] in any of its traits and 1 card with the [LIBERATOR] trait among them to the hand. Return the rest to the bottom of the deck. (Rule) Trait: Has [Aquatic] Type. --- Inherited: [End of Attack] [Once Per Turn] Gain 1 memory.
Lv.3 Sangomon BT19-017 U Rookie | Data | Mollusk/LIBERATOR [On Play] Reveal the top 3 cards of your deck. Add 1 card with [Aqua] or [Sea Animal] in one of its traits and 1 card with the [LIBERATOR] trait among them to the hand. Return the rest to the bottom of the deck. --- Inherited: [End of Attack] [Once Per Turn] Gain 1 memory.
Lv.3 サンゴモン BT19-017 U 成長期 | データ種 | 軟体型/リベレイター 【登場時】自分のデッキの上から3枚オープンする。その中の特徴に「水棲」を含むカード1枚と特徴に「リベレイター」を持つカード1枚を手札に加える。残りはデッキの下に戻す。 〈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]メモリー+1。