Feed the Swarm Destroy target creature or enchantment an opponent controls and you lose life equal to that permanents mana value Withering Torment Destroy target creature or enchantment
all aspects of the Colossuss ETB ability will resolve at once, so if you have a bounce land trigger on the stack, it wont resolve until you finish putting lands in and drawing cards
That up-front Adventure is just a bonus -- the real reward is outlasting the opponent with reanimation that draws from either graveyard, which is even better in "aristocrats" builds.
It's two game objects in one, specifically two foods for decks that need them, and its artifact animation effect lets you beat down with crumpets and cupcakes and such once you're in the lategame
Additionally, it means even if you run out of basics, you can still use the fetchlands for mana
You dont want to find yourself short on mana either, however, or youll be sitting there with no way to summon your amazing hand