Dell Conagher, Texian Genius

When Dell Conagher, Texian Genius enters
the battlefield choose one:
•Build a token Sentry
•Build a token Dispenser
•Build a token Teleporter
Create a token of the selected choice.
{3}{t}:Create a token of above choices
you have not already chosen.
When a token is destroyed,
it is able to be selected again.