Aetherdrift Tokens

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Foundations Tokens

Rin and Seri, Inseparable

Whenever you cast a Dog spell, create a 1/1 green Cat creature token.
Whenever you cast a Cat spell, create a 1/1 white Dog creature token.
{R}{G}{W}, {T}: Rin and Seri, Inseparable deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.

Whenever you cast a Dog spell, create a 1/1 green Cat creature token.
Whenever you cast a Cat spell, create a 1/1 white Dog creature token.
{R}{G}{W}, {T}: Rin and Seri deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.

Waiting in the Weeds

Each player counts the untapped forests he or she controls and puts that many 1/1 green Cat creature tokens into play.

Each player creates a 1/1 green Cat creature token for each untapped Forest they control.

Ajani, Adversary of Tyrants Emblem

At the beginning of your end step, create three 1/1 white Cat creature tokens with lifelink.