Draw instead of train cards; optionally discard to double a route's points

• Each player starts with 1 random terrain card
• 2 face-up terrain cards are available alongside the 5 face-up train cards
• On your turn, you may draw terrain cards instead of train cards
• 3 types: Desert/Savanna (warm routes: red, orange, yellow), Jungle/Forest (cool routes: green, blue, purple), Mountain/Cliff (grey-scale routes: black, white, grey)
• Terrain card type must match the color family of the route you are claiming
• 1 terrain card doubles points on 1–3 space routes; 2 terrain cards double points on 4–6 space routes
• Unused terrain cards at end of game are worth nothing