This is why (with few exceptions) any Reserved List card has at least some value nowadaysespecially any Reserved List card from Alpha , Beta , Unlimited , and even Revised
The effect is more and more noticeable as you go down the list of Mystery Booster cards and cross-reference that with amount of play on EDHREC
His ability to grant additional +1/+1 counters to humans each time another creature enters the battlefield underlines a strategy of cumulative strength
Rough and Tumble Creature (24) Asmodeus the Archfiend Black Dragon x2 Cleaving Reaper Cragplate Baloth Dauntless Survivor x4 Dragonsguard Elite Karfell Kennel-Master x2 Murasa Brute x3 Oran-Rief Ooze Scurrid Colony x3 Specter of the Fens x2 Vampire Spawn x3 Instant (6) Might of Murasa x4 Oblivion's Hunger x2 Sorcery (3) Rabid Bite x3 Land (27) Evolving Wilds x4 Forest x12 Swamp x11 There isnt a ton of synergy between the black and green cards in Rough and Tumble
There are other effects that draw cards when a creature dies, but none are as efficient or as easy to trigger as the token-munching Skullclamp
Pros And Cons Despite being a comical joke card and not technically being legal in any format, Nerf War is surprisingly pricey
