Just gonna leave this here. http://gatherer.wizards.com/Pages/Search/Default.aspx?action=advanced&color= ![W]+![G]&text=+![{w}]+![{g}]+![{b}]+![{u}]+![{r}]+![{t}]+![{2}]+![{3}]+![{4}]+![{5}]+![{6}]+![{7}]+![{8}]+![{9}]+![cycling]+![morph]+![transform]+![energy]+![equip]+![snow]+[:]&type=|[%22Artifact%22]|[%22Creature%22]
This a search for every creature and artifact in our colors that has an activated ability that Mairsil can use, does not cause Mairsil to tap, does not cost more than 1 mana, does not cost colored mana, and does not cost snow mana or use energy counters.
EDIT: For some reason it won't post the whole link, just copy/paste it. (sorry, no clue how to fix). Also forgot to omit soulbond and fortify, but those are rare enough. I also opted to leave in creatures with ETBs, which let in a few oddballs (namely eldrazi) but I didn't want to cut out cards that Mairsil could use that also synergize with Panharmonicon and the like.
http://gatherer.wizards.com/Pages/Search/Default.aspx?action=advanced&color= ![W]+![G]&text=+![{w}]+![{g}]+![{b}]+![{u}]+![{r}]+![{t}]+![{2}]+![{3}]+![{4}]+![{5}]+![{6}]+![{7}]+![{8}]+![{9}]+![cycling]+![morph]+![transform]+![energy]+![equip]+![snow]+[:]&type=|[%22Artifact%22]|[%22Creature%22]
This a search for every creature and artifact in our colors that has an activated ability that Mairsil can use, does not cause Mairsil to tap, does not cost more than 1 mana, does not cost colored mana, and does not cost snow mana or use energy counters.
EDIT: For some reason it won't post the whole link, just copy/paste it. (sorry, no clue how to fix). Also forgot to omit soulbond and fortify, but those are rare enough. I also opted to leave in creatures with ETBs, which let in a few oddballs (namely eldrazi) but I didn't want to cut out cards that Mairsil could use that also synergize with Panharmonicon and the like.