That said, it's one of those cards that's really easy to overestimate and I guess that's what happened here
For three mana, Hound Tamer is a 3/3 with trample that can put +1/+1 counters on creatures for four mana
Youre not building a zombie deck here, but the typical wheel-and-deal decks get a huge boost with Nekusar at the helm
Quest for Ulas Temple can get a counter, you can set up Sapling of Colfenor for a massive attack of life gain and draw the card, you can find abilities for Skill Borrower, play it with Garruks Horde, haste it out with Impromptu Raid, find a use for Descendants Path, and so forth
Vintage kept its restricted list, because some people wanted to play with powerful cards (and also because Type 1.5, aka legacy had started to take root, which, at the time, was just vintage with the restricted list renamed "banned list"), but in standard, you already couldn't play with all your cards, so there really wasn't any good reason to keep a restricted list
This ability can be especially fun in decks that focus on high-toughness creatures, letting them hit harder than usual, making Bill the Pony a flavorful and valuable addition
