My criteria for rating the thallids is (relatively) simple: First I look at the spore counter ability
You never really know what youre going to hit your opponent with
Creatures (32) 2 Jarad, Golgari Lich Lord 3 Lotleth Troll 2 Deathrite Shaman 4 Elvish Mystic 2 Shadowborn Demon 4 Sylvan Caryatid 4 Nighthowler 4 Nemesis of Mortals 3 Herald of Torment 4 Satyr Wayfinder Lands (20) Spells (8) Sideboard Lastly (at least for this article), Temple of Malady also opens up the opportunity for BUG decks to operate more effectively
The Royal Assassin's power even prevents the target creature from dealing damage since it is discarded before the Combat Damage Step is resolved
If, after removing some sequences which would lead to cards having U4 rarity, you end up with the sum of these maximum values (U2 and U3) amounting to 121, you likely have it figured out
While its unlikely to ever be made an official competitive title, even having online battles could pose a threat to the physical TCG