It's definitely a strange ability, but the gist of it is that connecting with your 3/3s will let you cast powerful spells for free, which will likely make it even easier to use Magar and connect in combat as the game goes on
This type of design works best in Limited where you can pick up multiple Webs, and the spider/Web combo has shown up in three separate Limited formats
Coming down as a hasty 5/5 for means you can deal some damage right away, but its the random options that can truly swing a game: putting three +1/+1 counters on target creature, putting a shield counter on target creature and gaining three life, or fighting another target creature a foe controls
Liliana, Untouched by Death Liliana, Untouched by Death is greatly held back by its reliance on zombies
Some of the best One Piece cards for this approach are the 6-cost Helmeppo and 7-cost Koby
I could think of a few commanders that you could slot this into if you wanted to bring some RL spice to your next games