A level 10 I-Rex is worse than a level 40 T-Rex.
The common rule is, if you can’t make two (for a level 20), don’t make the hybrid. (And you said you have the DNA for it. I just made mine and it was 500DNA per evolve try and I think it took 3 or 4 tries.)
I didn’t want to make the I-Rex until I had 2 level 40 T-Rexs. (I got lucky a few weeks ago and got like 3 copies in one week. No DNA spent for the second T-Rex.)
What is your current line up? Will 1x level 20 I-Rex be super strong and far out from the rest?
My top Dino is still a level 40 T-Rex. I’ve made a deep enough bench that I can safely finish in Dominator by saturday night. (I currently have a SUPER deep Jurassic bench and love it.) Some have much shallower and strong benches that work for them. And of my top 40 dinos, the Ferocity is within a few hundred, so they all work for smashing events.
You have to pick your goals in the game.
Is it a Dominator finish? How many times a day are you willing to battle? (My battle window is 3 times a day 7 hours apart. Some of my new dinos, even at level 1 are 8 hours now, so my window will soon have to evolve to maybe a 10 hour window for twice a day.)
Other people just want a lot of cool strong dinos.
We each can play how we want.
That much DNA is hard to come by. Right now, I have a few end game dinos unlocked and I’d rather spend 42K on one of those instead of 32K on an I-Rex, which is just really strong hybrid.
A different poster (maybe Han Solo?) said only spend DNA on things you need/want. The game will give you most of the rest.
The game doesn’t give you a lot of hybrids. (PvP modded gives you a few, but it is limited in types. Grinding PvP modded for the Rajastega is a good move. Be sure to have elite level prizes for best chances.)
I would tell you to carefully look over what you have unlocked and what hybrids you can unlock with your current unlocks. Evaluate which hybrids will help you the most.
For me, the big game changing hybrid unlock was the Ankylodocus because they take 1 day to hatch. They cost 11K DNA. But, I could make 6 in a week, 3x using the wednesday 15% discount and 3x more on Thursday’s discount window. (Or 2x and 2x if you are hatching something else.)
I could use a level 20 as a ok meat shield in dominator (1538H and 481A) and have a 7 hour cool down (supporting battling 3 times a day). They have enough health and attack, that if you need to swap or attack a bird, they can do it. I started finishing in Dom with 3x L20 of these guys (so they each fought 11 times for 33 times in a 3day 4hour tournment). At the same time, I had a Stegoceratops at level 20, 1410H 361A and it just didn’t work for me. He was one-shoted dead too much.
What I needed for my game to get better fast was a dino that I could get to work in Dominator at level 20. Level 30 (excluding the Diplotator, who is great at level 30) was just too much DNA/hatch time/evolve time to get me there in a couple of weeks.
Are you finishing in Dom? If not, what do you need to get there? 1 level 20 I-Rex will help, but 32k DNA and a level 40 T-rex is a lot to pay for that if you aren’t and need work.
Sorry for the long post. You may want to post your top 3 screens of dinos AND which hybrid dinos you have unlocked or can unlock. (Can unlock meaning you have the dinos to make them unlocked, but haven’t done it yet and may need more copies to get a level 40 to do it.)