I think you mean this guy:
http://gameinfo.na.leagueoflegends.com/en/game-info/champions/trundle/
Or maybe this guy:
http://dota2.gamepedia.com/Troll_Warlord
Bard looks more like this guy:
http://starcraft.wikia.com/wiki/Arbiter
I am definitely going to be calling the new hero Bard by the nickname of Arbiter in homage to Blizzard and Starcraft.
Also, if you really wanted to screw over your team with ability abuse, Dota 2 already has a lot of heroes to do that with.
http://dota2.gamepedia.com/Earthshaker
Trap your own teammates. Know Trundle's block of Ice? Imagine that but 15 to 20 times wider.
http://dota2.gamepedia.com/Shadow_Demon
Teammate trying to make a kill? No problem, just cast your duplication spell on the enemy and they are banished from the map. Free Zhonya's.
http://dota2.gamepedia.com/Io
Enemy team isn't farmed enough yet? No problem, just take your ally into the middle of 3-5 of the enemy while his spells are not ready or his mana is low, then break the tether, when they kill him, just come back and die, too. Pretend you got lost.
Those heroes are among some of the strongest ones in the game, the latter two because they are so flexible. If Valve removed the flexibility of those heroes, they wouldn't be as good. Riot shouldn't make champions worse for the sake of 'preventing abuse' since that is a punishment problem, not a design problem. As for the first one, he lacks synergy with a lot of heroes as you might imagine, but is really great with others. This is where the ban system and well-crafted drafts help keep the game fair.
If the game really gets so far out of hand as you are claiming, just be thankful he won't be 450 IP since he is a new champion.