Alistair, the Brigadier (Extended Art) [Doctor Who]

Description

Set:	Doctor Who
Type:	Legendary Creature — Human Soldier
Rarity:	Rare
Cost:	{1}{G}{W}{U}

Whenever you cast a historic spell, create a 1/1 white Soldier creature token. (Artifacts, legendaries, and Sagas are historic.)
Whenever Alistair attacks, you may pay {8}. If you do, creatures you control get +X/+X until end of turn, where X is the number of historic permanents you control.