For Commanders like The Unagi of Kyoshi Island and The Council of Four, Horn of Plenty acts as both a card advantage engine and a way to trigger your Commander
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You toss on counter on this when it deals damage, not two, but you can untap a land to make mana, force a target dork to not block, or toss a +1/+1 counter to perma-pump the equipped dork
While this won't allow you to cheat out too many hard hitters, you should be able to secure some great defenders or creatures that are costly thanks to their abilities
As noted earlier, the cards weren't initially perceived as collectibles
Take that lore and translate it into cardboard form, and you find a Commander unconcerned with specifics