Plus, it comes back to your hand when it dies, skirting around commander tax
The ability to bounce any permanent allows decks to cover their bases, gives you the option to position things early or in a waiting game by bouncing a land and it makes sure that you'll get to trigger the discard effect
Every element here works to allow you to outpace and out-damage anyone you come up against
To be sure, Nirkana Revenant will all but ensure that it will keep itself safe by doubling up on all your mana needs and giving you an outlet for all that extra mana
Going back, though, there's a noted dearth of interesting legends from this era that I'd love to see remedied and to have some get their time in the sun
And if the spirit knights ability doesnt end games, Moonshaker Calvary is still a 6/6 with Flying