Urza Assembles the Titans

After this Saga’s third chapter ability resolves, you may activate the same ability of a planeswalker twice that turn, or you may activate two different abilities of that planeswalker that turn.

As a Saga with read ahead enters the battlefield, its controller chooses a number from one to that Saga’s greatest chapter number. The Saga enters the battlefield with the chosen number of lore counters. Neither choosing the number nor putting the counters on the Saga use the stack, and neither can be responded to.

If more than one effect allows you to activate loyalty abilities of planeswalkers your control twice rather than only once, those effects don’t continue to increase the number of activations. You won’t be able to activate abilities of planeswalkers you control more than twice in a turn.