Aggressive decks want this effect and this card is five mana and requires three colors. Won't see play in D15.
This.
5/4 for 5 cmc that requires 3 colors isn't exactly good economy.
And the whole "can't block" thing seems wholly useless in the vast majority of matches.
Sure, it is a repeatable effect that can be triggered every turn, but it is also overall a pretty meh ability.
How often is it going to actually be relevant in a meta full of tokens and decks running cards like Visionary and Satyr Wayfinder?
If I wanted to play a dumb beater, I would prefer to be playing
Woolly Thoctar. It has the same P/T, costs 2 less, and isn't any more or less difficult on a decks mana base to be able to cast. Even in decks where Roughrider is at its best it still doesn't really compare.
Someone mentioned hitting it with
Deviant Glee to make it a 7/6 with pseudo Evasion. This is probably one of the better uses of the card. Even then, Thoctar often does the same thing but better.
Nimbus Wings on
Woolly Thoctar turns it into a 6/7 with Evasion, which isn't much worse than Roughrider, especially considering that it starts attacking in a full 2-3 turns before Roughrider does.
People also tend to forget that the ability requires attacking to trigger, which, due to what the ability does, usually doesn't pose much of a problem. It can certainly be a downside to the effect though. It isn't going to happen often, but there will be times when activating the ability means making bad attacks.
If I wanted an effect like that I would have much preferred something like
Bellowing Tanglewurm, which has the potential to actually win games as soon as it hits the table.
The only hope I had of the card actually doing something was dashed the moment I noticed that its type was "Orc Warrior", I was really hoping it was a Beast and thus could be worked into some sort of weird Glint-Eye Beast tribal deck alongside Woolly Thoctar but alas, that dream is dead.