Block phase: 4.b
Any card (except for a Wound) can be played sideways to the column as Block 1. Sideways cards are always physical Block, never a block of an elemental type.
Units can't be "played" as they're never in your hand. Instead they are "recruited" into a spot in front of you under one of your Command tokens.
2. At the start of the game, players control no Units. Units gained
(recruited) during the game are displayed in front of the player
in the Unit area at all times (they will never be in a player’s hand,
Deed deck or discard pile).