Most of the time this is immediate, as the effect that caused the trigger has finished resolving and the game checks to see what triggered to put it onto the stack
Rakdos Tree 4 Bloodtithe Harvester 4 Agatha's Soul Cauldron 4 Blackcleave Cliffs 4 Blightstep Pathway 4 Blood Crypt 4 Fable of the Mirror-Breaker 4 Fatal Push 4 Tree of Perdition 4 Voldaren Epicure 4 Voldaren Thrillseeker 4 Thoughtseize 3 Inti, Seneschal of the Sun 3 Mutavault 3 Raucous Theater 2 Swamp 2 Flamecache Gecko 1 Takenuma, Abandoned Mire 1 Mountain 1 Castle Locthwain 3 Path of Peril 3 Leyline of the Void 2 Duress 2 Laughing Jasper Flint 2 Ob Nixilis, the Adversary 2 Alpine Moon 1 Jegantha, the Wellspring Rakdos Tree shows that Sorin, Imperious Bloodlord plus Vein Ripper was not the only combo available for a black-red midrange deck
Suspicious Video Game Generosity: Seemingly played straight and then horribly subverted
The only limit to how many times you can retrace is if you can pay the resources to do so
Knights of San d'Oria (Ranger-Captain of Eos) Ranger-Captain of Eos sees enough Modern and Legacy play to warrant picking this one up
These are alternate art, specially treated cards which offer special variants on other, standard cards in any given set