A strong contender as one of the strongest Pokmon in the Base Set of the card game (after Charizard, of course), Venusaur is sought-after because of a variety of factors not the least of which is its ability to shuffle around Grass Energy like it was nothing, among the other cards in play under your control
Always keep an eye out for those big yellow price tags
Im sure you want to try a version of that in Commander, dont you
Ghoulcaller Gisa turns any big creature into a zombie horde, and you have plenty of big, big creatures, even without meaningful sacrifice or zombie synergies
Wall of Omens and Wall of Blossoms draw you an extra card no matter what, and two if you have your commander in play
This is an on-curve 6/6 for a splashable 6 mana with trample