Willow (Alyson Hannigan) started off as the wallflower good-buddy Scooby. Although they eventually let her sexuality out (in both senses), she was essentially stuck as good buddy for the entire run of the series.
Fortunately, there were two occasions when Alyson was given freer range. In the series three episode ‘The Wish’ a vengeance demon, Anyanka, grants Cordelia’s wish that Buffy had never come to down: bad move – the vampires, now including Willow, have taken over. Belatedly, a battle-scarred Buffy turns up to rescue the situation. Some episodes later in ‘Doppelgangland’ Anyanka and Willow cast a spell with unintending consequences – bringing the alternative reality (and somewhat confused) vampiric Willow into this world: she decides to go home and arrives just in time to meet the same stake that did for her in ‘The Wish’. Curiously, although the two episodes featuring the vampiric Willow were very close together in the same season, there appears to have been some inconsistency in the makeup: the orangey lenses of ‘The Wish’ being replaced by greenish contacts in ‘Doppelgangland’.
In series six Willow’s addiction to magic causes growing concern to the Scoobies. Tara’s death at the hands of the Nerds of Doom leaves Willow literally ‘Seeing Red’. An out-of-control very powerful and agry witch she becomes the Seasons Big Bad.
Robert Hall (Almost Human) was in charge of the makeup effects with Dayne Johnson as makeup supervisor.