Gideon's Lead the Charge ability does not trigger abilities that should trigger when a creature is summoned.
Steps to reproduce:
1. Play a game with Gideon having Centaur Sage in your deck.
2. Play Centaur Sage.
3. Play 2 or more creatures.
4. Assign at least 3 attackers.
5. Play Gideon's Lead the Charge.
Actual Results: Gideon, Battlefield Leader enters the arena, and Centaur Sage's ability does not trigger.
Expected Results: When played, Lead the Charge triggers abilities that are triggered when a friendly creature is summoned.
AdminWotC_Alan#83938 (Admin, Wizards of the Coast) shared this idea