Then each creature your opponents control gets -1/-1 until end of turn for each poison counter its controller has
As ever, evasion helps get damage through, but look at how you can leverage Menace and Vigilance in order to gain more tempo
Sonic and his friends come with a variety of interesting abilities to build around, and they're colored just right to include most of them in a deck with Sonic as the commander
Like so many colourless and EtB tapped lands I am happy enough playing one of these without other colourless and tapped lands
Similarly, if you sacrifice a creature to activate a mana ability while casting a spell with convoke, that creature wont be on the battlefield when you pay the spells costs, so you wont be able to tap it for convoke
If any of your opponents are running a deck built around a single creature type, the buff it provides will also be very helpful to them