One hidden element of this event is that you're allowed to skip the Colorless card reward, but forced to take a card if you choose 1 of 5 random cards (which come from your character's card pool). Because of this, it can be a little more appealing to look at Colorless cards, as long as you won't put yourself in immediate danger by paying the health. There are some very fun Colorless cards you can get early in the run this way. One of my favorites is Fasten, which lets basic defends remain strong throughout the entire run. Looking at five cards from your character's card pool isn't bad either, though!
Colorless cards tend to be slightly stronger than regular cards, so option 2 is my default here unless I can't afford the health loss. There's a good number of Power cards in the colorless pool which can give you quite a boost. Choosing from 5 regular cards can be worth it if you're trying to get a particular build going.
*ブスッ*
頭のてっぺんに鋭い痛みが走ったかと思うと、脳内に直接、奇妙な声が響いてきた。
「知識ヲ、共有スル？？」
さて、どうしたものか……
ヒルを引き剥がす
HPを5失う。 無色カード報酬を1枚受け取る。
頭に張り付いたヒルを力任せに引き剥がし、はるか彼方へと投げ捨てた！
頭の中に声が響く。
「ギャアアアアアァァァァァァァァ……！！」
知識を共有する
ランダムなカード5枚から1枚を選び、デッキに追加。
「迷宮ノ如キ精神ノ、ナント深淵ナル知識ノ泉カ！
マサニ我ガ脳髄ヲ満タス、極上ノフルコースダ！」
満足したのか、その生物はポンと頭から離れ、這い去っていった。
あなたはすっかり呆気にとられていた。