Entei thanks to Sacret Fire and Extreme Speed (event move, though).
Entei only got Sacred Fire in the most recent Generation, and it's impossible to have one with both Sacred Fire and Extremespeed (as the latter was a Gen 4 event). And, Entei has neither in the games you're most likely to get one in (ie. GSC and HGSS), anyways.
Pokemon that are terrible in at least competitive play:
- Phione (inferior Manaphi with a terrible movepool)
- Sunkern line (lowest base stats and terrible movepool)
- Unown (terrible stats, only one move)
- Chimecho (terrible stats, movepool)
- Luvdisk
- Ledian
Those are all bad in-game, too. Manaphy/Phione are impossible to obtain in normal gameplay, and the rest all have horrible stats and movepools that make them near-impossible to use.
It's true that Ice-typed Pokemon have unpractical common weaknesses and are a bit rough to use. I once went with a Glalie on Emerald, it was a bit odd and unpredictable, yet fun to play with (with Spikes/Toxic/Earthquake/Ice beam moveset).
Also, the painful truth is that most games have Dragon Pokemon as "final bosses" and these Dragons (or pseudo-legendaries) are sensitive to :
1. Ice-type moves
2. Dragon moves.
The problem with Ice types is that they're too rare, they show up too late, and most of them don't bring enough to the table to justify using either in-game or in competitive. Way too many of them have average stats, at best, have very limited movepools (usually just STAB and Normal moves), and their many weaknesses are just everywhere.
What makes it even worse is the fact that you don't even need an Ice type to actually have Ice moves. Ice Beam has been a readily-available TM since Gen 1 (with the exception of Gen 2), and
tons of non-Ice Pokémon can learn the move, including all but a few of the games'
most common type. Why bother going through the trouble of raising up an Ice type to take on that final Dragon Gym Leader or E4 member when you can just slap Ice Beam on the Water type you probably already have (thanks to Surf) and have something that can do more than just hit dragons and die to their Fire attacks?
So... Again we get to the questions "what is the point to all this" and "what did they have in mind" and "how could it be enhanced". In my opinion, story-mode suffers of more imbalance than competitive playing because of inefficient signature-moves or low-level move catastophies (Zubat, Kabuto, Tentacool, any anything that begins with Wrap or Constrict,...) among other things that just bug me. And that's a bit of unfair because competitive playing is quite a niche-y thing since many users won't even showup on the competitive scene, mostly because you need to be state-of-the-art and it costs some money and time.
I + or - understood that D/P battle network has been closed few monthes ago for instance, making it unavailable for late-players. Any ways, these non-competitive players stand to the game and eventually jump to a romhack and their dream is to catch and train and use very Pokemon line so they have the Dex Completed and a huge roster of lv. 100 full-efficience trained Pokemon (is it me I am talking about? yes. And I never got 100% of this aim because it's like utopy).
To me, the exploring/storytelling and the battling are very tied in the Pokemon game, and sometimes the combination of the two totally suck, I talk about big cave landscapes full of Zubats, repetitive wild Pokemon fights and grinding, 6-Pokemon team only, level-up straight game with no or few rematches and no possibility to build a new ingame team post-game or even mid-game (changing an, let's say, lv. 40 by a recently catched Pokemon, and grinding the newcomer afterwards, really is a hassle), doubtul Exp. gaining mechanics (that 1.5 bonus gave by trained Pokemon is stupid and would totally suck in RPGs such as FF)...
Fortunately, despite those negative points I listed, the game stays fascinating and fun to play, once you know what pleases you in story-mode. Some like to train their favourite Pokemon to the top no matter what their competitive value is, some feel like exploring, discovering secrets, some others like to breed... It's at least a very open game where you can do many things and that's good. My actual like has always been to beat the game super-effectively with Well-balanced type coverage teams.
Maybe in the future we will see a split between the classic story-mode games and a brand new battle-strategy-focused game (e.g. the more mature thread). It sure would be wise by my standards, but would it be well-marketed and then sold?
The hard truth is that Story Mode just isn't important in GF's mind anymore. While competitive battling truly was an obscure niche during the first 2-3 Gens, it exploded in popularity during the DS era (mostly thanks to wi-fi), and the competitive crowd has now become one of the largest and most vocal parts of the fandom, for better or worse. As a result, GF now concentrates most of their efforts to catering to the "metagame," often at the expense of Story Mode.
Just look at XY, for example. The story is very watered-down and none of the major NPCs are terribly strong or memorable, so the game is
very easy to button-mash through, especially with Exp. Share on. And, the postgame is pretty much limited to a battle facility, aka. a single-player version of competitive battling. And, most of the new features like Super Training, Friend Safari, the updated breeding mechanics, and even Mega Evolutions all have more value to competitive players than casual ones. The games basically entice you to drop your in-game team and get to work breeding/EV-ing up a new "perfect" one as soon as you beat the E4.
A part of me wishes that GF would just make their own battle simulator for competitive players, and let the main games be games again. Pokémon isn't supposed to be a glorified battle simulator with a story tacked on. IMO.