when mirage was about.. i dug flanking.. it was annoying, but not broken... echo as well. Phasing was stupid, as was morph.. i mean they made 2 cards meant to BREAK (dermoplasm, skirk alarmist) and it STILL wasnt all that amazing...
cycling is overdone.. hmm lets see... i'd welcome thallids, they were fun and took a long time
maybe a gold blue/green one with untargetability (to you only) that can let you take an extra turn...
maybe something like
3UG 1/4
at the beginning of your upkeep put a fungus counter on ~this~
remove 5: fungus counters, take an extra turn..
something like that would be respectable..
slivers need to die hard... they were even bad with the stupid new ones that cost 5 and 8 mana to cast.. stupid idea... too broken, the only thing that makes them difficult is using all duals.. whoopty.. anyone can do that nowadays..
turn 1: tundra, sliver
turn 2: volcanic island, crystalline sliver
turn 3: pain
turn 4: pain
turn 5: pain
eureka would be fun, but they kind of did that in dissention with that wierd ass green thing... he says ALL creatures.. i didnt even catch that!