Put Entei to sleep so that it's can't run away. If you only have one ultra ball, I'd recommend stocking up on more because the catch rate of any Legendary Pokemon is much less than a regular one.
Train a Golbat/Crobat. Or catch Entei with the Master Ball and randomly run into Raiku for the first time (Full HP) and catch with an Ultra Ball.
you can put it to sleep/paralyze it etc. than use 100+ ultra balls
Other than the masterball try using a lot of ultra balls.
A masterball would be the best choice but if you want to save it, you should use a Pokemon that does not let him flee (he always flees after the first turn) and use regular pokeballs or ultra balls
If its a Pokemon that runs away like entei, raikou and suicune weaken it when you find it when it shows up again it will still be weak now throw a ultra ball if you fail keep trying!
beat him to red then throw an ultra ball
Its easy just hurt it very much but not kilt paralyze the entei if you can or use hypnosis but you don't must to do that just make it easier. then use the ultra ball. I not sure the entei will be catch directly but soon.
you ensure that you catch the entei, but it will be harder to catch the ho-oh using ultra or other balls
The cipher admin Dakim has shadow entei to catch it weaken it to red HP and then paralyze it then use all the ultra balls you have.
if you do not have a masterball then use an ultra ball
Train a Golbat/Crobat. Or catch Entei with the Master Ball and randomly run into Raiku for the first time (Full HP) and catch with an Ultra Ball.
Neither is easier to catch than the other. They both have a catch rate of 3.
well get a Pokemon that knows hypnosis and mean look and after u make entei a sleep switch your Pokemon that knows a TM that lowers entei acurracy note after u switch entei will flee now go to entei again use mean look and then use hypnosis start hitting him to the red and throw a pokeball at him afer u do hold down L and R because it improves the succes. now if u want to catch raikou do the same thign now if u don't want to use the flowing master ball ultra ball great ball or pokeball use a net ball i tried to catch raikou with a ultra ball and don't work so i used a net ball and it worked better than a ultra ball but i didnt catch it so i havent got entei or raikou but i know what to do yo catch him
grow a pair... and get good pokemon to get the legendary pokemon's health low... then use an ultra ball over and over again until you catch it
You catch them with a ultra ball
save your master ball or get a tag from wabafet and give it to a Pokemon with strong light and has a par move or sleep move and get get him to red life and get lots of ultra balls ^u can try that but what i did was i would do is on fire red get a master ball from saffron city at the big building then make a Pokemon hold the master ball then trade the Pokemon into leagreen then when ever entei comes CATCH HIM WITH A MASTAAAAHH BAAAALLL!!!!
lol i just beat morty i went out the gate and entei appeared and i used a fast ball from kurt and caught it. fast balls, quick balls at the start of the battle and ultra balls.