All creature cards you own with flash are instants in addition to their other types.
Whenever you cast another spell with two or more card types, you may draw a card, then discard a card.
If you don’t draw a card, you don’t discard a card.
Some playtest cards have unusual type lines. To determine whether those cards have a card type not listed above, refer to that card’s rulings on Gatherer.wizards.com.
The card types that can normally appear on spells are artifact, creature, enchantment, instant, land, planeswalker, sorcery, and tribal. Legendary, basic, and snow are supertypes, not card types.