A option could be concentration check to controll the summoned creature... but if it is animal Int, or a concentration check to give a order to a sentient creature like a celestial champion.
Other idea is the "pet" class. When a summoned creature kills a enemy... the XPs rewards aren´t for the PCs but for the "pet class" like it was a extra PCs. Spending XPs like crafting magic item in the 3rd Edition the PCs can get improved familiars, animal companions, better skill to summoning magic, paladin´s mounts, the magic pets...
About summoned monsters I would mention the subgenre of magic pets, like Pokemon, Digimon, Huntik: Secrets & Seekers
, Bakugan, Monsuno
, monster rancher
where main characters can train or summon a monster or special creature to fight creatures controlled or guided by other humans.
WotC could a module about it, and if cards are played suitable,
if Wotc do it well, it could be a great sucess. en.wikipedia.org/wiki/Category:Creature_...
Can you imagine the D&D version of Dragon drive
What is your opinion about pathfinder summoner?
I would like a module about a "magic pet" with monster levels like "Savage Species" with customizable monster traits for leveling up.
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Book 13 Anaclet 23
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