You have 4 Upgrade markers, each of which you can use to upgrade any 1 of your Action cards. You can therefore upgrade all 4 Action cards during the course of the game if you meet all the conditions (you may upgrade several at once):

1. You have supported at least 1 Conservation objective.

2. You have at least 2 Projects in your zoo.

3. You have at least 3 connected tiles of a single habitat (, , or ) in your zoo.

4. You have at least 4 different Animal class icons in your zoo.

Carry out the following steps for each of your previously unused Upgrade markers whose condition you have met (which might be multiple markers, one right after the other):

1. Choose 1 of your Action cards that has not yet been upgraded.

2. Flip it from side I (upward pointing arrow on the left) to side II (upward pointing arrow on the right). This increases the strength of future actions and gives you more options.

3. Then turn the used Upgrade marker face down. You cannot use it again.

EXAMPLE: After you have played the Tree House in step 3., you have 3 connected tiles with a forest icon in your zoo (A). You have now met the condition of the “3 connected tiles of a single habitat” Upgrade marker and flip it over (B). This allows you to upgrade 1 of your Action cards and you decide to flip the Water Animals action card over to side II (C). This increases the strength of this action by 1 for the rest of the game. For example, if you were to use the Water Animals action on your next turn, it would have a strength of 4 (instead of 3 from before the upgrade) and you could play up to 2 Water animals (instead of just 1).