The number of card types matters, not the number of cards. For example, Wicker Witch (an artifact creature) along with Catalog (an instant) and Chaplainâ€™s Blessing (a sorcery) will enable delirium.
The card types in Magic are artifact, creature, enchantment, instant, land, planeswalker, sorcery, and tribal (a card type that appears on some older cards). Supertypes (such as legendary and basic) and subtypes (such as Human and Equipment) are not counted.
Losing or gaining first strike after first-strike damage has been dealt wonâ€™t cause Paranoid Parish-Blade to deal combat damage twice or to not deal combat damage.
In some rare cases, you can have a token or a copy of a spell in your graveyard at the moment that an objectâ€™s delirium ability counts the card types among cards in your graveyard, before that token or copy ceases to exist. Because tokens and copies of spells are not cards, even if they are copies of cards, their types will never be counted.
Because you consider only the characteristics of a double-faced cardâ€™s front face while itâ€™s not on the battlefield, the types of its back face wonâ€™t be counted for delirium.