How do you get a T-Rex in Ride A Pet?

It is a Dragon Egg gacha roll at 15 percent, which makes it the most reachable high-tier pet in that table. There is no pity timer, so a run without one is normal rather than broken, and the odds do not improve with failed attempts.

It depends which ladder you mean, and this is the clearest example of the problem on the whole roster. The Index prints 1 in 10T for it while the shop panel rolls it at 15 percent, which is one in under seven. Those two figures describe different systems rather than disagreeing about one.

How many rolls do I need for a T-Rex?

At 15 percent the average is under seven rolls, so a ten roll pack lands at least one about eighty times in a hundred. At the cheapest pack price in the table that works out to roughly 467 Robux of expected cost for a single T-Rex, against about a hundred rolls for the Dragon sitting at one percent in the same egg.

What else comes out of the same egg?

Crocodile at 50 percent and Fox at 30 percent, which between them account for eighty percent of every roll. That is the real cost of this gacha. You are not buying a T-Rex, you are buying a distribution, and four fifths of it is two mid-tier pets.

Is the T-Rex good for the egg loop?

It is fast without being the fastest, and its jump is exactly average for the roster, which is the part that matters. Speed decides how far you can travel and jump decides whether the ground in front of you is passable. A pet in the top five on speed with a median jump cannot reach everything a slower pet with a high jump can.

T-Rex - Stats and How to Get It

T-Rex at a glance

Base speed: 266K
Base jump: 100
Base income: 50,000%
Index rarity: 1 in 10T

Read the four cards together and a shape appears. The T-Rex is a top five pet on speed and on income, and it is exactly the median pet on jump. Two of those three numbers are excellent and one is the most ordinary value on the entire roster.

Pets carry four stats in this game: Speed, Jump, Income and Weight. Weight is reported as a flat 10 kg on every known pet, so it carries no information and is not published here. Jump controls terrain traversal: which ridges, steps and shortcuts a mount can use, and therefore which awkward spawn points are reachable. It is an absolute number, not a percentage, though no source defines its unit.

One pet, two rarity figures, and only one of them is about hatching

The Index prints 1 in 10T for this pet. The Dragon Egg shop panel rolls it at 15 percent, which is one in under seven. If those two figures described the same thing, one of them would be wrong by roughly a factor of one and a half trillion, and a game cannot ship that.

They describe two different systems. The Index label measures rarity within the map egg system. The shop panel publishes the odds of its own gacha. The two ladders rank pets in the same order and share no scale at all, which is why every pet that appears in both has two numbers that look like a contradiction and are not.

The practical consequence is narrower than it sounds and it matters a lot. If you want this pet, the map figure is irrelevant to you. You are buying rolls, so the only number that decides your spending is the fifteen percent. The full derivation of the two ladders is on the Phoenix page, which sits one tier above this pet in the same table.

What 15 percent actually costs

This is the good news about the T-Rex. It is the most reachable high-tier pet in the Dragon Egg table, and it is not close. At 15 percent the average is 6.7 rolls for a single hit, and a 10 roll pack lands at least one about 80 times in a hundred.

Expected cost of a T-Rex from the Dragon Egg compared with the tiers above it
Pet	Roll rate	Rolls for 10	Chance in one pack
Crocodile	50%	5.0	100%
Fox	30%	3.0	97%
T-Rex	15%	1.5	80%
Phoenix	4%	0.4	34%
Dragon	1%	0.1	10%

At the cheapest pack price in the table, 70 Robux per roll, the expected cost of a single T-Rex is about 467 Robux. Compare that with the Dragon in the same table, which sits at 1 percent and therefore needs about 100 rolls for the same expectation. That makes the Dragon roughly 15 times more expensive to obtain, which is a far bigger gap than the 3 rows that separate the two pets on the roster.

That last comparison is the point. On the rarity ladder the two pets are neighbours. On the shop panel they are more than an order of magnitude apart in what they cost to actually get. Any guide that quotes the Index label as though it predicted the roll price has read one ladder and reported it as the other.

That comparison is the whole reason this pet is interesting. On the rarity ladder it looks unreachable, sitting at 1 in 10T. On the shop panel it is the last tier of that gacha that a normal player should expect to actually hit.

What you are really buying

A gacha is not a purchase, it is a distribution, and this table is the honest version of what a 10roll pack contains. The expected values add up to the pack size, which is a good sign the published odds are internally consistent, and the shape of the column is the part worth reading.

Expected composition of a ten roll Dragon Egg pack
Pet	Roll rate	Expected in 10 rolls
Crocodile	50%	5.0
Fox	30%	3.0
T-Rex	15%	1.5
Phoenix	4%	0.4
Dragon	1%	0.1

Eighty percent of a pack is two mid-tier pets. That is the real price of the T-Rex, and it is not measured in Robux. The pets that appear alongside it are Crocodile and Fox, which sit far down the roster and are worth roughly what their hatch rate suggests, so a session spent chasing the T-Rex is mostly a session spent filling a ranch with two pets you did not want.

There is a fair argument that this is fine, because those pets feed the Index and can be mutated like any other. There is also a fair argument that the table is designed so the top 20 percent is what you are paying for and the rest is volume. Both readings describe the same numbers, and this page is not going to pretend one of them is neutral.

The jump problem, which is the part that decides routes

A top five speed rating is worth less than it sounds once you look at the third stat. Base jump decides which ridges, steps and shortcuts a mount can use, and therefore which awkward spawn points are reachable at all. The T-Rex sits at 100, which is number 15 of 30 and puts it exactly in the middle of the roster.

That combination is unusual and it has a specific consequence. A pet that is fast but average on jump is a pet that wins on open ground and loses on terrain, which means the routes it cannot run are not the slow ones, they are the ones behind a ledge. Several cheaper pets beat it on jump, including Spider at 129 and Kangaroo at 125, so owning the T-Rex does not retire them.

The T-Rex ranked against the roster on all three axes
Axis	T-Rex	Rank	Leader
Base speed	266K	5 of 30	Kitsune
Base jump	100	15 of 30	Kitsune
Base income	50,000%	5 of 30	Dragon

A buyer’s instinct is to treat a top five ranking as a top five pet. This table is what that instinct costs. Two of those ranks are genuinely strong, one is average, and the average one governs where you can go. The T-Rex is a good pet that is easy to overrate, and the overrating happens because most rankings score one axis instead of three.

What is still not established about this pet

Shifted up one row by the _rarityConflict.
Whether the Index label of this pet is affected by the same one-row offset that runs from Ostrich upward. If it is, the printed figure belongs to another pet.
Whether the map egg route to this pet exists at all, since only the shop gacha has published odds.
What the income percentage column is a percentage of, which prevents the figure from being converted into an amount of cash per second.
Whether the Dragon Egg gacha odds are the same on every server and whether they change with updates, since no patch notes are published.

Common questions

How do you get a T-Rex in Ride A Pet?: It is a Dragon Egg gacha roll at 15 percent, which makes it the most reachable high-tier pet in that table. There is no pity timer, so a run without one is normal rather than broken, and the odds do not improve with failed attempts.
Is the T-Rex rare?: It depends which ladder you mean, and this is the clearest example of the problem on the whole roster. The Index prints 1 in 10T for it while the shop panel rolls it at 15 percent, which is one in under seven. Those two figures describe different systems rather than disagreeing about one.
How many rolls do I need for a T-Rex?: At 15 percent the average is under seven rolls, so a ten roll pack lands at least one about eighty times in a hundred. At the cheapest pack price in the table that works out to roughly 467 Robux of expected cost for a single T-Rex, against about a hundred rolls for the Dragon sitting at one percent in the same egg.
What else comes out of the same egg?: Crocodile at 50 percent and Fox at 30 percent, which between them account for eighty percent of every roll. That is the real cost of this gacha. You are not buying a T-Rex, you are buying a distribution, and four fifths of it is two mid-tier pets.
Is the T-Rex good for the egg loop?: It is fast without being the fastest, and its jump is exactly average for the roster, which is the part that matters. Speed decides how far you can travel and jump decides whether the ground in front of you is passable. A pet in the top five on speed with a median jump cannot reach everything a slower pet with a high jump can.