How to make that players can choice the ability

[Mr. Gameplay Knowledge]

How to make that player can choice the abilitys for heros like in the map the chosen ones,please can you help me?

 

[Light]

i forgot how the chosen ones's abilities work, haven't played it in a long time q_q

if you have to buy them from a shop, make a dummy item for the ability then make a trigger that when a unit buys an item and bought item is equal to dummy item, remove the dummy item then add the ability to the unit.

 

[Mr. Gameplay Knowledge]

Cool, thanks!!